Coatings containing multiple drugs

Information

  • Patent Grant
  • 9737645
  • Patent Number
    9,737,645
  • Date Filed
    Tuesday, December 15, 2015
    8 years ago
  • Date Issued
    Tuesday, August 22, 2017
    7 years ago
Abstract
A method for depositing a coating comprising a polymer and at least two pharmaceutical agents on a substrate, comprising the following steps: providing a stent framework; depositing on said stent framework a first layer comprising a first pharmaceutical agent; depositing a second layer comprising a second pharmaceutical agent; Wherein said first and second pharmaceutical agents are selected from two different classes of pharmaceutical agents.
Description
BACKGROUND OF THE INVENTION

The present invention relates to methods for depositing a coating comprising a polymer and a pharmaceutical or biological agent in powder form onto a substrate.


It is often beneficial to provide coatings onto substrates, such that the surfaces of such substrates have desired properties or effects.


For example, it is useful to coat biomedical implants to provide for the localized delivery of pharmaceutical or biological agents to target specific locations within the body, for therapeutic or prophylactic benefit. One area of particular interest is that of drug eluting stents (DES) that has recently been reviewed by Ong and Serruys in Nat. Clin. Pract. Cardiovasc. Med., (December 2005), Vol 2, No 12, 647. Typically such pharmaceutical or biological agents are co-deposited with a polymer. Such localized delivery of these agents avoids the problems of systemic administration, which may be accompanied by unwanted effects on other parts of the body, or because administration to the afflicted body part requires a high concentration of pharmaceutical or biological agent that may not be achievable by systemic administration. The coating may provide for controlled release, including long-term or sustained release, of a pharmaceutical or biological agent. Additionally, biomedical implants may be coated with materials to provide beneficial surface properties, such as enhanced biocompatibility or lubriciousness.


Conventionally, coatings have been applied by processes such as dipping, spraying, vapor deposition, plasma polymerization, and electro-deposition. Although these processes have been used to produce satisfactory coatings, there are drawbacks associated therewith. For example it is often difficult to achieve coatings of uniform thicknesses and prevent the occurrence of defects (e.g. bare spots). Also, in many processes, multiple coating steps are frequently necessary, usually requiring drying between or after the coating steps.


Another disadvantage of most conventional methods is that many pharmaceutical or biological agents, once deposited onto a substrate, suffer from poor bioavailability, reduced shelf life, low in vivo stability or uncontrollable elution rates, often attributable to poor control of the morphology and/or secondary structure of the agent. Pharmaceutical agents present significant morphology control challenges using existing spray coating techniques, which conventionally involve a solution containing the pharmaceutical agents being spayed onto a substrate. As the solvent evaporates the agents are typically left in an amorphous state. Lack of or low degree of crystallinity of the spray coated agent can lead to decreased shelf life and too rapid drug elution. Biological agents typically rely, at least in part, on their secondary, tertiary and/or quaternary structures for their activity. While the use of conventional solvent-based spray coating techniques may successfully result in the deposition of a biological agent upon a substrate, it will often result in the loss of at least some of the secondary, tertiary and/or quaternary structure of the agent and therefore a corresponding loss in activity. For example, many proteins lose activity when formulated in carrier matrices as a result of the processing methods.


Conventional solvent-based spray coating processes are also hampered by inefficiencies related to collection of the coating constituents onto the substrate and the consistency of the final coating. As the size of the substrate decreases, and as the mechanical complexity increases, it grows increasingly difficult to uniformly coat all surfaces of a substrate.


What is needed is a cost-effective method for depositing inert polymers and pharmaceutical or biological agents onto a substrate, where the collection process is efficient, the coating produced is conformal, substantially defect-free and uniform, the composition of the coating can be regulated and the morphology and/or secondary structure of the pharmaceutical or biological agents can be controlled. The method would thus permit structural and morphological preservation of the agents deposited during the coating process.


SUMMARY OF THE INVENTION

A first aspect of the invention provides methods for depositing a coating comprising a polymer and pharmaceutical agent on a substrate, comprising discharging at least one pharmaceutical agent in a therapeutically desirable morphology in dry powder form through a first orifice; discharging at least one polymer in dry powder form through a second orifice; depositing the polymer and/or pharmaceutical particles onto said substrate, wherein an electrical potential is maintained between the substrate and the pharmaceutical and/or polymer particles, thereby forming said coating; and sintering said coating under conditions that do not substantially modify the morphology of said pharmaceutical agent.


Although the size, resistivity and moisture content of the polymer and pharmaceutical agent may vary widely based on the conditions used, desired particle sizes are typically in the range of 0.01 μm-2500 μm, and more preferably in the range of 0.01 μm-100 μm, resistivity is typically in the range of from about 106 Ωm to about 1024 Ωm and moisture content is less than 5% by weight. In one embodiment of the invention the molecular weight range of the polymer is from about 5,000 a.u. to about 100,000 a.u. In other embodiments, the first and second orifices are provided as one single orifice wherein the pharmaceutical agent and polymer may be mixed together prior to discharging. In yet other embodiments the pharmaceutical agent and polymer particles may be discharged simultaneously or in succession. In another embodiment of the invention the method further comprises discharging a third dry powder comprising a second pharmaceutical agent whereby a coating comprising at least two different pharmaceutical agents is deposited on said substrate. In some embodiments, the therapeutically desirable morphology of said pharmaceutical agent is crystalline or semi-crystalline, wherein preferably at least 50% of said pharmaceutical agent in powder form is crystalline or semicrystalline. In certain other embodiments of the invention the pharmaceutical agent is prepared by milling, jet-milling, granulation, spray drying, crystallizing or fluidizing and in a preferred embodiment the therapeutically desirable morphology is not substantially changed after the step of sintering the coating. In a further embodiment the pharmaceutical agent and/or the polymer becomes electrostatically charged prior to deposition, and the substrate may be electrically grounded. In a preferred embodiment, the substrate is electrostatically charged. In some embodiments the polymer and pharmaceutical agent are discharged using a gas based propellant, which typically comprises carbon dioxide, nitrous oxide, hydrofluorocarbons, chlorofluorocarbons, helium, nitrogen, compressed air, argon, or volatile hydrocarbons with a vapor pressure greater than 750 Torr at 20° C., and is preferably carbon dioxide. In one embodiment of the invention the pharmaceutical agent comprises at least one drug, which may be selected from Sirolimus, Tacrolimus, Everolimus, Zotarolimus, and Taxol. In another embodiment of the invention the ratio of pharmaceutical agent to polymer is from about 1:50 to about 5:1. In some embodiments, the amount of pharmaceutical agent will depend on the particular agent being employed, the type of substrate, and the medical condition being treated. Typically, the amount of pharmaceutical agent is about 0.001 percent to about 70 percent, more typically about 0.001 percent to about 50 percent, most typically about 0.001 percent to about 20 percent by weight of the polymer/pharmaceutical agent combination. In other embodiments, however, the present invention permits “high load” formulation where the coating composition comprises at least 50, 60, 70 or 80 percent by weight of the pharmaceutical agent, combined with not more than 50, 40, 30 or 20 percent by weight of polymer composition.


Another aspect of the invention provides methods for depositing a coating comprising an active biological agent and a polymer on a substrate, comprising discharging at least one active biological agent through a first orifice; discharging at least one polymer in dry powder form through a second orifice; depositing the active biological agent and/or polymer particles onto said substrate, wherein an electrical potential is maintained between the substrate and the active biological agent and/or polymer particles, thereby forming said coating; and sintering said coating under conditions that do not substantially modify the activity of said biological agent.


In some embodiments the activity of the active biological agent is of therapeutic or prophylactic value and may be influenced by its secondary, tertiary or quaternary structure. In a preferred embodiment of the invention, the active biological agent possesses a secondary, tertiary or quaternary structure which is not substantially changed after sintering. In one embodiment of the invention the active biological agent is a peptide, protein, enzyme, nucleic acid, antisense nucleic acid, antimicrobial, vitamin, hormone, steroid, lipid, polysaccharide or carbohydrate, and may further comprise a stabilizing agent. Most preferably the active biological agent is a peptide, protein or enzyme. In other embodiments, the active biological agent is provided as a dry powder Although the size, resistivity and moisture content of the active biological agent and polymer may vary widely based on the conditions used, desired particle sizes are typically in the range of 0.01 μm-2500 μm, and more preferably in the range of 0.01 μm-100 μm, resistivity is typically in the range of from about 106 Ωm to about 1024 Ωm and moisture content is less than 5% by weight. In one embodiment of the invention the molecular weight range of the polymer is from about 5,000 a.u. to about 100,000 a.u. In other embodiments, the first and second orifices are provided as one single orifice wherein the pharmaceutical agent and polymer may be mixed together prior to discharging. In yet other embodiments the pharmaceutical agent and polymer particles may be discharged simultaneously or in succession. In another embodiment of the invention the method further comprises discharging a second active biological agent whereby a coating comprising at least two different biological agents is deposited on said substrate. In a further embodiment the biological agent and/or the polymer becomes electrostatically charged prior to deposition, and the substrate may be electrically grounded. In a preferred embodiment, the substrate is electrostatically charged. In some embodiments the polymer and biological agent are discharged using a gas based propellant, which typically, comprises carbon dioxide, nitrous oxide, hydrofluorocarbons, chlorofluorocarbons, helium, nitrogen, compressed air or volatile hydrocarbons with a vapor pressure greater than 750 Torr at 20° C., and is preferably carbon dioxide. In another embodiment of the invention the ratio of biological agent to polymer is from about 1:50 to about 5:1. In some embodiments, the amount of biological agent will depend on the particular agent being employed, the type of substrate, and the medical condition being treated. Typically, the amount of biological agent is about 0.001 percent to about 70 percent, more typically about 0.001 percent to about 50 percent, most typically about 0.001 percent to about 20 percent by weight of the polymer/biological agent combination. In other embodiments, however, the present invention permits “high load” formulation where the coating composition comprises at least 50, 60, 70 or 80 percent by weight of the biological agent, combined with not more than 50, 40, 30 or 20 percent by weight of polymer composition.


Yet another aspect of the invention provides methods for depositing a coating comprising a polymer and a pharmaceutical agent on a substrate, comprising discharging at least one pharmaceutical agent in a therapeutically desirable morphology in dry powder form through a first orifice; forming a supercritical or near supercritical fluid mixture that includes at least one supercritical fluid solvent and at least one polymer and discharging said supercritical or near supercritical fluid solution through a second orifice under conditions sufficient to form solid particles of the polymer; depositing the polymer and/or pharmaceutical particles onto said substrate, wherein an electrical potential is maintained between the substrate and the pharmaceutical and/or polymer particles, thereby forming said coating and sintering said coating under conditions that do not substantially modify the morphology of said solid pharmaceutical particles.


Although the size, resistivity and moisture content of the pharmaceutical agent may vary widely based on the conditions used, desired particle sizes are typically in the range of 0.01 μm-2500 μm, and more preferably in the range of 0.01 μm-100 μm, resistivity is typically in the range of from about 106 Ωm to about 1024 Ωm and moisture content is less than 5% by weight. In one embodiment of the invention, the molecular weight range of the polymer is from about 5,000 a.u. to about 100,000 a.u. In one embodiment of the invention the pharmaceutical and polymer particles are discharged simultaneously, while in another embodiment of the invention they are discharged in succession. In another embodiment of the invention the method further comprises discharging a second dry powder comprising a second pharmaceutical agent whereby a coating comprising at least two different pharmaceutical agents is deposited on said substrate. In some embodiments, the therapeutically desirable morphology of said pharmaceutical agent is crystalline or semi-crystalline, wherein preferably at least 50% of said pharmaceutical agent in powder form is crystalline or semicrystalline. In certain other embodiments of the invention the pharmaceutical agent is prepared by milling, jet-milling, granulation, spray drying, crystallizing or fluidizing and in a preferred embodiment the therapeutically desirable morphology is not substantially changed after the step of sintering the coating. In a further embodiment the pharmaceutical agent and/or the polymer becomes electrostatically charged prior to deposition, and the substrate may be electrically grounded. In a preferred embodiment, the substrate is electrostatically charged. In some embodiments the pharmaceutical agent is discharged using a gas based propellant, which typically comprises carbon dioxide, nitrous oxide, hydrofluorocarbons, chlorofluorocarbons, helium, nitrogen, compressed air or volatile hydrocarbons with a vapor pressure greater than 750 Torr at 20° C., and is preferably carbon dioxide. In one embodiment of the invention the pharmaceutical agent comprises at least one drug, which may be selected from [list]. In another embodiment of the invention the ratio of pharmaceutical agent to polymer is from about 1:50 to about 5:1. In some embodiments, the amount of pharmaceutical agent will depend on the particular agent being employed, the type of substrate, and the medical condition being treated. Typically, the amount of pharmaceutical agent is about 0.001 percent to about 70 percent, more typically about 0.001 percent to about 50 percent, most typically about 0.001 percent to about 20 percent by weight of the polymer/pharmaceutical agent combination. In other embodiments, however, the present invention permits “high load” formulation where the coating composition comprises at least 50, 60, 70 or 80 percent by weight of the pharmaceutical agent, combined with not more than 50, 40, 30 or 20 percent by weight of polymer composition.


A further aspect of the invention provides methods for depositing a coating comprising an active biological agent and a polymer on a substrate, comprising discharging at least one active biological agent through a first orifice; forming a supercritical or near supercritical fluid mixture that includes at least one supercritical fluid solvent and at least one polymer and discharging said supercritical or near supercritical fluid solution through a second orifice under conditions sufficient to form solid particles of the polymer; depositing the active biological agent and/or polymer particles onto said substrate, wherein an electrical potential is maintained between the substrate and the active biological agent and/or polymer particles, thereby forming said coating and sintering said coating under conditions that do not substantially modify the activity of said biological agent.


In some embodiments the activity of the active biological agent is of therapeutic or prophylactic value and may be influenced by its secondary, tertiary or quaternary structure. In a preferred embodiment of the invention, the active biological agent possesses a secondary, tertiary or quaternary structure which is not substantially changed after sintering. In one embodiment of the invention the active biological agent is a peptide, protein, enzyme, nucleic acid, antisense nucleic acid, antimicrobial, vitamin, hormone, steroid, lipid, polysaccharide or carbohydrate, and may further comprise a stabilizing agent. Most preferably the active biological agent is a peptide, protein or enzyme. In other embodiments, the active biological agent is provided as a dry powder. Although the size, resistivity and moisture content of the active biological agent may vary widely based on the conditions used, desired particle sizes are typically in the range of 0.01 μm-2500 μm, and more preferably in the range of 0.01 μm-100 μm, resistivity is typically in the range of from about 106 Ωm to about 1024 Ωm and moisture content is less than 5% by weight. In one embodiment of the invention the molecular weight range of the polymer is from about 5,000 a.u. to about 100,000 a.u. In one embodiment of the invention the biological agent and polymer particles are discharged simultaneously, while in another embodiment of the invention they are discharged in succession. In another embodiment of the invention the method further comprises discharging second active biological agent whereby a coating comprising at least two different biological agents is deposited on said substrate. In a further embodiment the biological agent and/or the polymer becomes electrostatically charged prior to deposition, and the substrate may be electrically grounded. In a preferred embodiment, the substrate is electrostatically charged. In some embodiments the biological agent is discharged using a gas based propellant, which typically comprises carbon dioxide, nitrous oxide, hydrofluorocarbons, chlorofluorocarbons, helium, nitrogen, compressed air or volatile hydrocarbons with a vapor pressure greater than 750 Torr at 20° C., and is preferably carbon dioxide. In another embodiment of the invention the ratio of biological agent to polymer is from about 1:50 to about 5:1. In some embodiments, the amount of biological agent will depend on the particular agent being employed, the type of substrate, and the medical condition being treated. Typically, the amount of biological agent is about 0.001 percent to about 70 percent, more typically about 0.001 percent to about 50 percent, most typically about 0.001 percent to about 20 percent by weight of the polymer/biological agent combination. In other embodiments, however, the present invention permits “high load” formulation where the coating composition comprises at least 50, 60, 70 or 80 percent by weight of the biological agent, combined with not more than 50, 40, 30 or 20 percent by weight of polymer composition.


Each of the above methods may be carried out from about 0° C. to about 80° C. and from about 0.1 atmospheres to about 73 atmospheres, in either open or closed vessel. In some embodiments, the substrate is a biomedical implant which may be a stent, electrode, catheter, lead, implantable pacemaker or cardioverter housing, joint, screw, rod, ophthalmic implant, prosthetic or shunt.


In some embodiments of the invention the thickness of said coating is from about 1 to about 100 μm, preferably about 10 μm, and the variation in the thickness along said coating is within 0.5 μm, within 0.25 μm, within 0.1 μm or within 10% of the total thickness of said coating, within 5% of the total thickness of said coating, or within 2.5% of the total thickness of said coating. In other embodiments, the XRD pattern of said pharmaceutical agent or active biological agent comprises at least two, at least five and preferably at least ten of the same peaks after the coating process, as compared to the XRD pattern of said pharmaceutical agent or active biological agent prior to the coating process. In yet other embodiments, the pharmaceutical agent or active biological agent is positioned at a selected distance from top of said coating. In further embodiments, the pharmaceutical agent or active biological agent is positioned at about midway between the top of said coating and the substrate surface. In other embodiments of the invention the variability in the amount of pharmaceutical agent or active biological agent deposited on said substrate is 20% or less, 15% or less, 10% or less, 5% or less, for a batch of substrates coated at the same time. Preferably the variability is 5% or less. In yet other embodiments of the invention, the methods further comprise depositing a top layer on said coating wherein said top layer is a polymer film. In some embodiments, the polymer film has a thickness of 0.5 to 10 microns, and can be deposited by a RESS or SEDS process. In yet other embodiments, the polymer film is formed by depositing a single polymer and can be formed by depositing substantially pure PBMA.


The invention further relates to the use of a supercritical solution comprising a second fluid in its supercritical state.


In some embodiments, the addition of a second fluid in its supercritical state is to act as a flammability suppressor. In other embodiments, a second fluid is used, wherein said second fluid has critical parameters lower than the first fluid's critical parameters, and therefore lowers the critical properties of the mixture/solution enabling access to the mixture supercritical state.


In some embodiments the supercritical solution comprises isobutylene. In other embodiments, the supercritical fluid comprises isobutylene and carbon dioxide as a second fluid.


Other embodiments of the invention provide a way to dissolve two polymers in a supercritical solvent. In some embodiments said two polymers are PEVA and PBMA. In other embodiments, a supercritical solution comprising two polymers is used to create a RESS spray of the polymers generating ˜10 to 100 nm particles of each polymer. In further embodiments, PEVA and PBMA are dissolved in a supercritical solvent that further comprises CO2 to act as a fire suppressor in the event of an ignition source causing a fire.


INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.





BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:



FIG. 1. Schematic Representation of the Coating and Sintering Process Apparatus, as discussed in example 9.



FIG. 2. Detailed images of the Coating and Sintering Process Apparatus, as discussed in example 9.



FIG. 3. Drug-Polymer coated coronary stent (a) immediately after deposition, (b) after annealing in a dense carbon dioxide environment at 40° C.; the photographs correspond to the experiment discussed in conjunction with Example 10.



FIG. 4. 40× Magnified Images of Rapamycin/PEVA/PBMA Coated Stents, Obtained From an Optical Microscope with Back and Side Lighting, Showing the Outside, Edge and Inside Surfaces, (a) before and (b) after sintering, as discussed in example 10.



FIG. 5. 40× Magnified Images of Rapamycin/PEVA/PBMA Coated Stents, Obtained From an Optical Microscope with Back and Side Lighting, Showing the Outside and Inside Surfaces, (a) before and (b) after sintering, as discussed in example 10.



FIG. 6. 100× Magnified Image of a Rapamycin/PEVA/PBMA Coated Stent, Obtained From an Optical Microscope. Crystalline drug is clearly visible embedded within a highly uniform polymer coating, as discussed in example 10.



FIG. 7. Scanning Electron Microscope Images of Rapamycin/PEVA/PBMA Coated Stents, at (a) ×30 magnification, (b) ×250 magnification, (c) ×1000 magnification and (d) ×3000 magnification, as discussed in example 11.



FIG. 8. Cross-sectional Scanning Electron Microscope Images of Rapamycin/PEVA/PBMA Coated Stents at (a) ×7000 magnification and (b) ×20000 magnification. Four cross-sectional thicknesses measured: (1) 10.355 μM; (2) 10.412 μM; (3) 10.043 μM and (4) 10.157 μM, providing a calculated average thickness of 10.242 μM ±2%, also discussed in example 11.



FIG. 9. Differential Scanning calorimetry (DSC) of (a) PEVA Control, (b) PBMA Control, (c) Rapamycin Control and (d) Coated Rapamycin, PEVA, PBMA Mixture. The Rapamycin crystalline melt at 185-200° C. is indicated in (c) and (d), as discussed in example 12.



FIG. 10. X-Ray Diffraction of (a) Microionized Rapamycin Powder (Control) and (b) Coated Sintered Rapamycin/PEVA/PBMA Stents, as discussed in example 13.



FIG. 11. Confocal Raman Analysis of Rapamycin/PEVA/PBMA Coated Stents (i.e. Depth Profiling from Coating Surface to Metal Stent), highlighting (a) Rapamycin Depth Profile Outside Circumference and (b) Polymer Depth Profile Outside Circumference, as discussed in example 14.



FIG. 12. (a) Rapamycin UV-Vis Spectrum and (b) Calibration Curve at 277 nm, (c) PEVA/PBMA FT-IR Spectrum, (d) PEVA Calibration Curve at 1050 nm and (e) PBMA Calibration Curve at 1285 nm.



FIG. 13. Quantification of Coating Components, (mean concentrations (3 stents each); 4 cell by 8 mm parylene coated). (a) Rapamycin Quantification (74±11 μg) Using UV-Vis Method; (b) PEVA (1060±190 μg) and (c) PBMA (1110±198 μg) Quantification Using FT-IR Method, as discussed in example 15.



FIG. 14. Optical Microscopy Showing the Outside Surface of a 3 mm Guidant TriStar® Stent Coated with Paclitaxel-polymer composite, as discussed in example 16.



FIG. 15. Paclitaxel Quantification After Coating on a 3 mm Guidant TriStar® Stent with Paclitaxel/PEVA/PMBA composite, as discussed in example 16. (a) Calibration Curve at 228 nm in ethanol Using UV-Vis Standard Method and (b) Quantification (148±14 μg) Using UV-Vis Method



FIG. 16. Quantification of Coating Components, (mean concentrations (3 stents each); 6 cell by 8 mm parylene coated). (a) Rapamycin Quantification (81±3 μg) Using UV-Vis Method; (b) PEVA (391±69 μg) and (c) PBMA (268±64 μg) Quantification Using FT-IR Method, as discussed in example 17.



FIG. 17. Cloud point isotherms for polyethylene-co-vinyl acetate (PEVA) and poly(butyl methacrylate) (PMBA) combined as discussed in examples 19, 20, 21 and 22.



FIGS. 18-24 illustrate particular embodiments of the invention





DETAILED DESCRIPTION OF THE INVENTION

The present invention is explained in greater detail below. This description is not intended to be a detailed catalog of all the different ways in which the invention may be implemented, or all the features that may be added to the instant invention. For example, features illustrated with respect to one embodiment may be incorporated into other embodiments, and features illustrated with respect to a particular embodiment may be deleted from that embodiment. In addition, numerous variations and additions to the various embodiments suggested herein will be apparent to those skilled in the art in light of the instant disclosure, which do not depart from the instant invention. Hence, the following specification is intended to illustrate some particular embodiments of the invention, and not to exhaustively specify all permutations, combinations and variations thereof.


Applicants specifically intend that all United States patent references cited herein be incorporated herein by reference in their entirety.


The present invention provides a cost-effective, efficient method for depositing a combination of an inert polymer or polymers and a pharmaceutical or biological agent or agents, onto parts or all surfaces of a substrate, to form a coating that is of a pre-determined, desired thickness, conformal, substantially defect-free, and uniform and the composition of the coating can be regulated. In particular, the present invention addresses the problem of existing coating processes, which do not allow for structural and morphological preservation of the agents deposited during the coating process.


The first aspect of the invention entails the deposition of the pharmaceutical or biological agents as dry powders, using electrostatic capture to attract the powder particles to the substrate. Dry powder spraying is well known in the art, and dry powder spraying coupled with electrostatic capture has been described, for example in U.S. Pat. Nos. 5,470,603 6,319,541 or 6,372,246. The deposition of the polymer can be performed in any number of standard procedures, as the morphology of the polymer, so long as it provides coatings possessing the desired properties (e.g. thickness, conformity, defect-free, uniformity etc), is of less importance. The function of the polymer is primarily one of inert carrier matrix for the active components of the coating.


The second step of the coating process involves taking the substrates that have been coated with pharmaceutical or biological agents and polymers and subjecting them to a sintering process that takes place under benign conditions, which do not affect the structural and morphological integrity of the pharmaceutical and biological agents. The sintering process as used in the current invention refers to the process by which the co-deposited pharmaceutical agent or biological agent-polymer matrix, becomes fused and adherent to the substrate by treatment of the coated substrate with a compressed gas, compressed liquid, or supercritical fluid that is a non-solvent for the polymers, the pharmaceutical agents and the biological agents, but a plasticizing agent for the polymer. The sintering process takes place under conditions (e.g. mild temperatures), and using benign fluids (e.g. supercritical carbon dioxide) which will not affect the structural and morphological integrity of the pharmaceutical and biological agents.


One aspect of the invention is the combination of two or more of the dry powder, RESS and SEDS spraying techniques. In all aspects of the invention a pharmaceutical or biological agent is deposited onto a substrate by dry powder spraying.


A specific aspect of the invention involves the dry powder spraying of a pharmaceutical agent, in a preferred particle size and morphology, into the same capture vessel as a polymer that is also dry powder sprayed, whereby the spraying of the agent and the polymer is sequential or simultaneous.


Another specific aspect of the invention involves the dry powder spraying of an active biological agent, in a preferred particle size and possessing a particular activity, into the same capture vessel as a polymer that is also dry powder sprayed, whereby the spraying of the agent and the polymer is sequential or simultaneous.


Yet another aspect of the invention involves the dry powder spraying of a pharmaceutical agent, in a preferred particle size and morphology, into the same capture vessel as a polymer that is sequentially or simultaneously sprayed by the RESS spray process.


Yet another aspect of the invention involves the dry powder spraying of an active biological agent, in a preferred particle size and possessing a particular activity, into the same capture vessel as a polymer that is sequentially or simultaneously sprayed by the RESS spray process.


Yet another aspect of the invention involves the dry powder spraying of a pharmaceutical agent, in a preferred particle size and morphology, into the same capture vessel as a polymer that is sequentially or simultaneously sprayed by the SEDS spray process.


Yet another aspect of the invention involves the dry powder spraying of an active biological agent, in a preferred particle size and possessing a particular activity, into the same capture vessel as a polymer that is sequentially or simultaneously sprayed by the SEDS spray process.


Any combination of the above six processes is contemplated by this aspect of the invention.


In further aspects of the invention the substrates that have been coated with pharmaceutical or biological agents and polymers, as described in the above embodiments are then subjected to a sintering process. The sintering process takes place under benign conditions, which do not affect the structural and morphological integrity of the pharmaceutical and biological agents, and refers to a process by which the co-deposited pharmaceutical agent or biological agent-polymer matrix, becomes fused and adherent to the substrate. This is achieved by treating the coated substrate with a compressed gas, compressed liquid or supercritical fluid that is a non-solvent for the polymers, the pharmaceutical agents and the biological agents, but a plasticizing agent for the polymer. The sintering process takes place under conditions (e.g. mild temperatures), and using benign fluids (e.g. supercritical carbon dioxide) which will not affect the structural and morphological integrity of the pharmaceutical and biological agents. Other sintering processes, which do not affect the structural and morphological integrity of the pharmaceutical and biological agents may also be contemplated by the present invention.


DEFINITIONS

As used in the present specification, the following words and phrases are generally intended to have the meanings as set forth below, except to the extent that the context in which they are used indicates otherwise.


“Substrate” as used herein, refers to any surface upon which it is desirable to deposit a coating comprising a polymer and a pharmaceutical or biological agent, wherein the coating process does not substantially modify the morphology of the pharmaceutical agent or the activity of the biological agent. Biomedical implants are of particular interest for the present invention; however the present invention is not intended to be restricted to this class of substrates. Those of skill in the art will appreciate alternate substrates that could benefit from the coating process described herein, such as pharmaceutical tablet cores, as part of an assay apparatus or as components in a diagnostic kit (e.g. a test strip).


“Biomedical implant” as used herein refers to any implant for insertion into the body of a human or animal subject, including but not limited to stents (e.g., vascular stents), electrodes, catheters, leads, implantable pacemaker, cardioverter or defibrillator housings, joints, screws, rods, ophthalmic implants, femoral pins, bone plates, grafts, anastomotic devices, perivascular wraps, sutures, staples, shunts for hydrocephalus, dialysis grafts, colostomy bag attachment devices, ear drainage tubes, leads for pace makers and implantable cardioverters and defibrillators, vertebral disks, bone pins, suture anchors, hemostatic barriers, clamps, screws, plates, clips, vascular implants, tissue adhesives and sealants, tissue scaffolds, various types of dressings (e.g., wound dressings), bone substitutes, intraluminal devices, vascular supports, etc.


The implants may be formed from any suitable material, including but not limited to organic polymers (including stable or inert polymers and biodegradable polymers), metals, inorganic materials such as silicon, and composites thereof, including layered structures with a core of one material and one or more coatings of a different material. However, the invention contemplates the use of electrostatic capture in conjunction with substrate having low conductivity or which non-conductive. To enhance electrostatic capture when a non-conductive substrate is employed, the substrate is processed while maintaining a strong electrical field in the vicinity of the substrate.


Subjects into which biomedical implants of the invention may be applied or inserted include both human subjects (including male and female subjects and infant, juvenile, adolescent, adult and geriatric subjects) as well as animal subjects (including but not limited to dog, cat, horse, monkey, etc.) for veterinary purposes.


In a preferred embodiment the biomedical implant is an expandable intraluminal vascular graft or stent (e.g., comprising a wire mesh tube) that can be expanded within a blood vessel by an angioplasty balloon associated with a catheter to dilate and expand the lumen of a blood vessel, such as described in U.S. Pat. No. 4,733,665 to Palmaz.


“Pharmaceutical agent” as used herein refers to any of a variety of drugs or pharmaceutical compounds that can be used as active agents to prevent or treat a disease (meaning any treatment of a disease in a mammal, including preventing the disease, i.e. causing the clinical symptoms of the disease not to develop; inhibiting the disease, i.e. arresting the development of clinical symptoms; and/or relieving the disease, i.e. causing the regression of clinical symptoms). It is possible that the pharmaceutical agents of the invention may also comprise two or more drugs or pharmaceutical compounds. Pharmaceutical agents, include but are not limited to antirestenotic agents, antidiabetics, analgesics, antiinflammatory agents, antirheumatics, antihypotensive agents, antihypertensive agents, psychoactive drugs, tranquillizers, antiemetics, muscle relaxants, glucocorticoids, agents for treating ulcerative colitis or Crohn's disease, antiallergics, antibiotics, antiepileptics, anticoagulants, antimycotics, antitussives, arteriosclerosis remedies, diuretics, proteins, peptides, enzymes, enzyme inhibitors, gout remedies, hormones and inhibitors thereof, cardiac glycosides, immunotherapeutic agents and cytokines, laxatives, lipid-lowering agents, migraine remedies, mineral products, otologicals, anti parkinson agents, thyroid therapeutic agents, spasmolytics, platelet aggregation inhibitors, vitamins, cytostatics and metastasis inhibitors, phytopharmaceuticals, chemotherapeutic agents and amino acids. Examples of suitable active ingredients are acarbose, antigens, beta-receptor blockers, non-steroidal antiinflammatory drugs {NSAIDs], cardiac glycosides, acetylsalicylic acid, virustatics, aclarubicin, acyclovir, cisplatin, actinomycin, alpha- and beta-sympatomimetics, (dmeprazole, allopurinol, alprostadil, prostaglandins, amantadine, ambroxol, amlodipine, methotrexate, S-aminosalicylic acid [sic], amitriptyline, amoxicillin, anastrozole, atenolol, azathioprine, balsalazide, beclomethasone, betahistine, bezafibrate, bicalutamide, diazepam and diazepam derivatives, budesonide, bufexamac, buprenorphine, methadone, calcium salts, potassium salts, magnesium salts, candesartan, carbamazepine, captopril, cefalosporins, cetirizine, chenodeoxycholic acid, ursodeoxycholic acid, theophylline and theophylline derivatives, trypsins, cimetidine, clarithromycin, clavulanic acid, clindamycin, clobutinol, clonidine, cotrimoxazole, codeine, caffeine, vitamin D and derivatives of vitamin D, colestyramine, cromoglicic acid, coumarin and coumarin derivatives, cysteine, cytarabine, cyclophosphamide, ciclosporin, cyproterone, cytabarine, dapiprazole, desogestrel, desonide, dihydralazine, diltiazem, ergot alkaloids, dimenhydrinate, dimethyl sulphoxide, dimeticone, domperidone and domperidan derivatives, dopamine, doxazosin, doxorubizin, doxylamine, dapiprazole, benzodiazepines, diclofenac, glycoside antibiotics, desipramine, econazole, ACE inhibitors, enalapril, ephedrine, epinephrine, epoetin and epoetin derivatives, morphinans, calcium antagonists, irinotecan, modafinil, orlistat, peptide antibiotics, phenytoin, riluzoles, risedronate, sildenafil, topiramate, macrolide antibiotics, oestrogen and oestrogen derivatives, progestogen and progestogen derivatives, testosterone and testosterone derivatives, androgen and androgen derivatives, ethenzamide, etofenamate, etofibrate, fenofibrate, etofylline, etoposide, famciclovir, famotidine, felodipine, fenofibrate, fentanyl, fenticonazole, gyrase inhibitors, fluconazole, fludarabine, fluarizine, fluorouracil, fluoxetine, flurbiprofen, ibuprofen, flutamide, fluvastatin, follitropin, formoterol, fosfomicin, furosemide, fusidic acid, gallopamil, ganciclovir, gemfibrozil, gentamicin, ginkgo, Saint John's wort, glibenclamide, urea derivatives as oral antidiabetics, glucagon, glucosamine and glucosamine derivatives, glutathione, glycerol and glycerol derivatives, hypothalamus hormones, goserelin, gyrase inhibitors, guanethidine, halofantrine, haloperidol, heparin and heparin derivatives, hyaluronic acid, hydralazine, hydrochlorothiazide and hydrochlorothiazide derivatives, salicylates, hydroxyzine, idarubicin, ifosfamide, imipramine, indometacin, indoramine, insulin, interferons, iodine and iodine derivatives, isoconazole, isoprenaline, glucitol and glucitol derivatives, itraconazole, ketoconazole, ketoprofen, ketotifen, lacidipine, lansoprazole, levodopa, levomethadone, thyroid hormones, lipoic acid and lipoic acid derivatives, lisinopril, lisuride, lofepramine, lomustine, loperamide, loratadine, maprotiline, mebendazole, mebeverine, meclozine, mefenamic acid, mefloquine, meloxicam, mepindolol, meprobamate, meropenem, mesalazine, mesuximide, metamizole, metformin, methotrexate, methylphenidate, methylprednisolone, metixene, metoclopramide, metoprolol, metronidazole, mianserin, miconazole, minocycline, minoxidil, misoprostol, mitomycin, mizolastine, moexipril, morphine and morphine derivatives, evening primrose, nalbuphine, naloxone, tilidine, naproxen, narcotine, natamycin, neostigmine, nicergoline, nicethamide, nifedipine, niflumic acid, nimodipine, nimorazole, nimustine, nisoldipine, adrenaline and adrenaline derivatives, norfloxacin, novamine sulfone, noscapine, nystatin, ofloxacin, olanzapine, olsalazine, omeprazole, omoconazole, ondansetron, oxaceprol, oxacillin, oxiconazole, oxymetazoline, pantoprazole, paracetamol, paroxetine, penciclovir, oral penicillins, pentazocine, pentifylline, pentoxifylline, perphenazine, pethidine, plant extracts, phenazone, pheniramine, barbituric acid derivatives, phenylbutazone, phenytoin, pimozide, pindolol, piperazine, piracetam, pirenzepine, piribedil, piroxicam, pramipexole, pravastatin, prazosin, procaine, promazine, propiverine, propranolol, propyphenazone, prostaglandins, protionamide, proxyphylline, quetiapine, quinapril, quinaprilat, ramipril, ranitidine, reproterol, reserpine, ribavirin, rifampicin, risperidone, ritonavir, ropinirole, roxatidine, roxithromycin, ruscogenin, rutoside and rutoside derivatives, sabadilla, salbutamol, salmeterol, scopolamine, selegiline, sertaconazole, sertindole, sertralion, silicates, sildenafil, simvastatin, sitosterol, sotalol, spaglumic acid, sparfloxacin, spectinomycin, spiramycin, spirapril, spironolactone, stavudine, streptomycin, sucralfate, sufentanil, sulbactam, sulphonamides, sulfasalazine, sulpiride, sultamicillin, sultiam, sumatriptan, suxamethonium chloride, tacrine, tacrolimus, taliolol, tamoxifen, taurolidine, tazarotene, temazepam, teniposide, tenoxicam, terazosin, terbinafine, terbutaline, terfenadine, terlipressin, tertatolol, tetracyclins, teryzoline, theobromine, theophylline, butizine, thiamazole, phenothiazines, thiotepa, tiagabine, tiapride, propionic acid derivatives, ticlopidine, timolol, tinidazole, tioconazole, tioguanine, tioxolone, tiropramide, tizanidine, tolazoline, tolbutamide, tolcapone, tolnaftate, tolperisone, topotecan, torasemide, antioestrogens, tramadol, tramazoline, trandolapril, tranylcypromine, trapidil, trazodone, triamcinolone and triamcinolone derivatives, triamterene, trifluperidol, trifluridine, trimethoprim, trimipramine, tripelennamine, triprolidine, trifosfamide, tromantadine, trometamol, tropalpin, troxerutine, tulobuterol, tyramine, tyrothricin, urapidil, ursodeoxycholic acid, chenodeoxycholic acid, valaciclovir, valproic acid, vancomycin, vecuronium chloride, Viagra, venlafaxine, verapamil, vidarabine, vigabatrin, viloazine, vinblastine, vincamine, vincristine, vindesine, vinorelbine, vinpocetine, viquidil, warfarin, xantinol nicotinate, xipamide, zafirlukast, zalcitabine, zidovudine, zolmitriptan, zolpidem, zoplicone, zotipine and the like. In some non-limiting examples, the pharmaceutical agent is rapamycin, a rapamycin analogue such as for example, zatarolimus, tacrolimus, or everolimus, estradiol, lantrunculin D, cytochalasin A, NO, dexamethasone, paclitaxel, and angiopeptin. See, e.g., U.S. Pat. No. 6,897,205; see also U.S. Pat. No. 6,838,528; U.S. Pat. No. 6,497,729 Examples of therapeutic agents employed in conjunction with the invention include, rapamycin, 40-O-(2-Hydroxyethyl)rapamycin (everolimus), 40-O-Benzyl-rapamycin, 40-O-(4′-Hydroxymethyl)benzyl-rapamycin, 40-O-[4′-(1,2-Dihydroxyethyl)]benzyl-rapamycin, 40-O-Allyl-rapamycin, 40-O-[3′-(2,2-Dimethyl-1,3-dioxolan-4(S)-yl)-prop-2′-en-1′-yl]-rapamycin, (2′:E,4′S)-40-O-(4′,5′-Dihydroxypent-2′-en-1′-yl)-rapamycin 40-O-(2-Hydroxy)ethoxycar-bonylmethyl-rapamycin, 40-O-(3-Hydroxy)propyl-rapamycin 40-O-(6-Hydroxy)hexyl-rapamycin 40-O-[2-(2-Hydroxy)ethoxy]ethyl-rapamycin 4O—O-[(3S)-2,2-Dimethyldioxolan-3-yl]methyl-rapamycin, 40-O-[(2S)-2,3-Dihydroxyprop-1-yl]-rapamycin, 4O—O-(2-Acetoxy)ethyl-rapamycin 4O—O-(2-Nicotinoyloxy)ethyl-rapamycin, 4O—O-[2-(N-Morpholino)acetoxy]ethyl-rapamycin 4O—O-(2-N-Imidazolylacetoxy)ethyl-rapamycin, 40-O-[2-(N-Methyl-N′-piperazinyl)acetoxy]ethyl-rapamycin, 39-O-Desmethyl-39,40-O,O-ethylene-rapamycin, (26R)-26-Dihydro-40-O-(2-hydroxy)ethyl-rapamycin, 28-O-Methyl-rapamycin, 4O—O-(2-Aminoethyl)-rapamycin, 4O—O-(2-Acetaminoethyl)-rapamycin 4O—O-(2-Nicotinamidoethyl)-rapamycin, 4O—O-(2-(N-Methyl-imidazo-2′-ylcarbethoxamido)ethyl)-rapamycin, 4O—O-(2-Ethoxycarbonylaminoethyl)-rapamycin, 40-O-(2-Tolylsulfonamidoethyl)-rapamycin, 40-O-[2-(4′,5′-Dicarboethoxy-1′,2′,3′-triazol-1′-yl)-ethyl]-rapamycin, 42-Epi-(tetrazolyl)rapamycin (tacrolimus), 42-[3-hydroxy-2-(hydroxymethyl)-2-methylpropanoate]rapamycin (temsirolimus), and and 40-epi-(N1-tetrazolyl)-rapamycin (zotarolimus).


The active ingredients may, if desired, also be used in the form of their pharmaceutically acceptable salts or derivatives (meaning salts which retain the biological effectiveness and properties of the compounds of this invention and which are not biologically or otherwise undesirable), and in the case of chiral active ingredients it is possible to employ both optically active isomers and racemates or mixtures of diastereoisomers.


“Stability” as used herein in refers to the stability of the drug in a polymer coating deposited on a substrate in its final product form (e.g., stability of the drug in a coated stent). The term stability will define 5% or less degradation of the drug in the final product form.


“Active biological agent” as used herein refers to a substance, originally produced by living organisms, that can be used to prevent or treat a disease (meaning any treatment of a disease in a mammal, including preventing the disease, i.e. causing the clinical symptoms of the disease not to develop; inhibiting the disease, i.e. arresting the development of clinical symptoms; and/or relieving the disease, i.e. causing the regression of clinical symptoms). It is possible that the active biological agents of the invention may also comprise two or more active biological agents or an active biological agent combined with a pharmaceutical agent, a stabilizing agent or chemical or biological entity. Although the active biological agent may have been originally produced by living organisms, those of the present invention may also have been synthetically prepared, or by methods combining biological isolation and synthetic modification. By way of a non-limiting example, a nucleic acid could be isolated form from a biological source, or prepared by traditional techniques, known to those skilled in the art of nucleic acid synthesis. Furthermore, the nucleic acid may be further modified to contain non-naturally occurring moieties. Non-limiting examples of active biological agents include peptides, proteins, enzymes, glycoproteins, nucleic acids (including deoxyribonucleotide or ribonucleotide polymers in either single or double stranded form, and unless otherwise limited, encompasses known analogues of natural nucleotides that hybridize to nucleic acids in a manner similar to naturally occurring nucleotides), antisense nucleic acids, fatty acids, antimicrobials, vitamins, hormones, steroids, lipids, polysaccharides, carbohydrates and the like. They further include, but are not limited to, antirestenotic agents, antidiabetics, analgesics, antiinflammatory agents, antirheumatics, antihypotensive agents, antihypertensive agents, psychoactive drugs, tranquillizers, antiemetics, muscle relaxants, glucocorticoids, agents for treating ulcerative colitis or Crohn's disease, antiallergics, antibiotics, antiepileptics, anticoagulants, antimycotics, antitussives, arteriosclerosis remedies, diuretics, proteins, peptides, enzymes, enzyme inhibitors, gout remedies, hormones and inhibitors thereof, cardiac glycosides, immunotherapeutic agents and cytokines, laxatives, lipid-lowering agents, migraine remedies, mineral products, otologicals, anti parkinson agents, thyroid therapeutic agents, spasmolytics, platelet aggregation inhibitors, vitamins, cytostatics and metastasis inhibitors, phytopharmaceuticals and chemotherapeutic agents. Preferably, the active biological agent is a peptide, protein or enzyme, including derivatives and analogs of natural peptides, proteins and enzymes.


“Activity” as used herein refers to the ability of a pharmaceutical or active biological agent to prevent or treat a disease (meaning any treatment of a disease in a mammal, including preventing the disease, i.e. causing the clinical symptoms of the disease not to develop; inhibiting the disease, i.e. arresting the development of clinical symptoms; and/or relieving the disease, i.e. causing the regression of clinical symptoms). Thus the activity of a pharmaceutical or active biological agent should be of therapeutic or prophylactic value.


“Secondary, tertiary and quaternary structure” as used herein are defined as follows. The active biological agents of the present invention will typically possess some degree of secondary, tertiary and/or quaternary structure, upon which the activity of the agent depends. As an illustrative, non-limiting example, proteins possess secondary, tertiary and quaternary structure. Secondary structure refers to the spatial arrangement of amino acid residues that are near one another in the linear sequence. The α-helix and the β-strand are elements of secondary structure. Tertiary structure refers to the spatial arrangement of amino acid residues that are far apart in the linear sequence and to the pattern of disulfide bonds. Proteins containing more than one polypeptide chain exhibit an additional level of structural organization. Each polypeptide chain in such a protein is called a subunit. Quaternary structure refers to the spatial arrangement of subunits and the nature of their contacts. For example hemoglobin consists of two α and two β chains. It is well known that protein function arises from its conformation or three dimensional arrangement of atoms (a stretched out polypeptide chain is devoid of activity). Thus one aspect of the present invention is to manipulate active biological agents, while being careful to maintain their conformation, so as not to lose their therapeutic activity.


“Polymer” as used herein, refers to a series of repeating monomeric units that have been cross-linked or polymerized. Any suitable polymer can be used to carry out the present invention. It is possible that the polymers of the invention may also comprise two, three, four or more different polymers. In some embodiments, of the invention only one polymer is used. In some preferred embodiments a combination of two polymers are used. Combinations of polymers can be in varying ratios, to provide coatings with differing properties. Those of skill in the art of polymer chemistry will be familiar with the different properties of polymeric compounds. Examples of polymers that may be used in the present invention include, but are not limited to polycarboxylic acids, cellulosic polymers, proteins, polypeptides, polyvinylpyrrolidone, maleic anhydride polymers, polyamides, polyvinyl alcohols, polyethylene oxides, glycosaminoglycans, polysaccharides, polyesters, bacterial polyesters (PHB, PHV), polyurethanes, polystyrenes, copolymers, silicones, polyorthoesters, polyanhydrides, copolymers of vinyl monomers, polycarbonates, polyethylenes, polypropylenes, polylactic acids, polyglycolic acids, polycaprolactones, polyhydroxybutyrate valerates, polyacrylamides, polyethers, polyurethane dispersions, polyacrylates, acrylic latex dispersions, polyacrylic acid, mixtures and copolymers thereof. The polymers of the present invention may be natural or synthetic in origin, including gelatin, chitosan, dextrin, cyclodextrin, Poly(urethanes), Poly(siloxanes) or silicones, Poly(acrylates) such as poly(methyl methacrylate), poly(butyl methacrylate), and Poly(2-hydroxy ethyl methacrylate), Poly(vinyl alcohol) Poly(olefins) such as poly(ethylene), poly(isoprene), halogenated polymers such as Poly(tetrafluoroethylene)—and derivatives and copolymers such as those commonly sold as Teflon® products, Poly(vinylidene fluoride), Poly(vinyl acetate), Poly(vinyl pyrrolidone), Poly(acrylic acid), Polyacrylamide, Poly(ethylene-co-vinyl acetate), Poly(ethylene glycol), Poly(propylene glycol), Poly(methacrylic acid), Poly(dimethyl)-siloxane, Polyethylene terephthalate, Polyethylene-vinyl acetate copolymer (PEVA), Ethylene vinyl alcohol (EVAL), Ethylene vinyl acetate (EVA), Poly(styrene-b-isobutylene-b-styrene) (SIBBS), Phosophorycholine (PC), styrene-isobutylene, fluorinated polymers, polyxylenes (PARYLENE), tyrosine based polycarbonates, tyrosine based polyarylates, poly(trimethylene carbonate), hexafluoropropylene, vinylidene fluoride, butyl methacrylate, hexyl methacrylate, vinyl pyrrolidinone, vinyl acetate, etc. Suitable polymers also include absorbable and/or resorbable polymers including the following, combinations, copolymers and derivatives of the following: Polylactides (PLA), Polyglycolides (PGA), Poly(lactide-co-glycolides) (PLGA), Polyanhydrides, Polyorthoesters, Poly(N-(2-hydroxypropyl) methacrylamide), Poly(l-aspartamide), Polyhydro-butyrate/-valerate copolymer, Polyethyleneoxide/polybutylene terephthalate copolymer, etc.


“Therapeutically desirable morphology” as used herein refers to the gross form and structure of the pharmaceutical agent, once deposited on the substrate, so as to provide for optimal conditions of ex vivo storage, in vivo preservation and/or in vivo release. Such optimal conditions may include, but are not limited to increased shelf life, increased in vivo stability, good biocompatibility, good bioavailability or modified release rates. Typically, for the present invention, the desired morphology of a pharmaceutical agent would be crystalline or semi-crystalline, although this may vary widely depending on many factors including, but not limited to, the nature of the pharmaceutical agent, the disease to be treated/prevented, the intended storage conditions for the substrate prior to use or the location within the body of any biomedical implant. Preferably at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100% of the pharmaceutical agent is in crystalline or semi-crystalline form.


“Stabilizing agent” as used herein refers to any substance that maintains or enhances the stability of the biological agent. Ideally these stabilizing agents are classified as Generally Regarded As Safe (GRAS) materials by the US Food and Drug Administration (FDA). Examples of stabilizing agents include, but are not limited to carrier proteins, such as albumin, gelatin, metals or inorganic salts. Pharmaceutically acceptable excipient that may be present can further be found in the relevant literature, for example in the Handbook of Pharmaceutical Additives: An International Guide to More Than 6000 Products by Trade Name, Chemical, Function, and Manufacturer; Michael and Irene Ash (Eds.); Gower Publishing Ltd.; Aldershot, Hampshire, England, 1995.


“Compressed fluid” as used herein refers to a fluid of appreciable density (e.g., >0.2 g/cc) that is a gas at standard temperature and pressure. “Supercritical fluid”, “near-critical fluid”, “near-supercritical fluid”, “critical fluid”, “densified fluid” or “densified gas” as used herein refers to a compressed fluid under conditions wherein the temperature is at least 80% of the critical temperature of the fluid and the pressure is at least 50% of the critical pressure of the fluid.


Examples of substances that demonstrate supercritical or near critical behavior suitable for the present invention include, but are not limited to carbon dioxide, isobutylene, ammonia, water, methanol, ethanol, ethane, propane, butane, pentane, dimethyl ether, xenon, sulfur hexafluoride, halogenated and partially halogenated materials such as chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, perfluorocarbons (such as perfluoromethane and perfluoropropane, chloroform, trichloro-fluoromethane, dichloro-difluoromethane, dichloro-tetrafluoroethane) and mixtures thereof.


“Sintering” as used herein refers to the process by which parts of the matrix or the entire polymer matrix becomes continuous (e.g., formation of a continuous polymer film). As discussed below, the sintering process is controlled to produce a fully conformal continuous matrix (complete sintering) or to produce regions or domains of continuous coating while producing voids (discontinuities) in the matrix. As well, the sintering process is controlled such that some phase separation is obtained between polymer different polymers (e.g., polymers A and B) and/or to produce phase separation between discrete polymer particles. Through the sintering process, the adhesions properties of the coating are improved to reduce flaking of detachment of the coating from the substrate during manipulation in use. As described below, in some embodiments, the sintering process is controlled to provide incomplete sintering of the polymer matrix. In embodiments involving incomplete sintering, a polymer matrix is formed with continuous domains, and voids, gaps, cavities, pores, channels or, interstices that provide space for sequestering a therapeutic agent which is released under controlled conditions. Depending on the nature of the polymer, the size of polymer particles and/or other polymer properties, a compressed gas, a densified gas, a near critical fluid or a super-critical fluid may be employed. In one example, carbon dioxide is used to treat a substrate that has been coated with a polymer and a drug, using dry powder and RESS electrostatic coating processes. In another example, isobutylene is employed in the sintering process. In other examples a mixture of carbon dioxide and isobutylene is employed.


When an amorphous material is heated to a temperature above its glass transition temperature, or when a crystalline material is heated to a temperature above a phase transition temperature, the molecules comprising the material are more mobile, which in turn means that they are more active and thus more prone to reactions such as oxidation. However, when an amorphous material is maintained at a temperature below its glass transition temperature, its molecules are substantially immobilized and thus less prone to reactions. Likewise, when a crystalline material is maintained at a temperature below its phase transition temperature, its molecules are substantially immobilized and thus less prone to reactions. Accordingly, processing drug components at mild conditions, such as the deposition and sintering conditions described herein, minimizes cross-reactions and degradation of the drug component. One type of reaction that is minimized by the processes of the invention relates to the ability to avoid conventional solvents which in turn minimizes autoxidation of drug, whether in amorphous, semi-crystalline, or crystalline form, by reducing exposure thereof to free radicals, residual solvents and autoxidation initiators.


“Rapid Expansion of Supercritical Solutions” or “RESS” as used herein involves the dissolution of a polymer into a compressed fluid, typically a supercritical fluid, followed by rapid expansion into a chamber at lower pressure, typically near atmospheric conditions. The rapid expansion of the supercritical fluid solution through a small opening, with its accompanying decrease in density, reduces the dissolution capacity of the fluid and results in the nucleation and growth of polymer particles. The atmosphere of the chamber is maintained in an electrically neutral state by maintaining an isolating “cloud” of gas in the chamber. Carbon dioxide or other appropriate gas is employed to prevent electrical charge is transferred from the substrate to the surrounding environment.


“Bulk properties” properties of a coating including a pharmaceutical or a biological agent that can be enhanced through the methods of the invention include for example: adhesion, smoothness, conformality, thickness, and compositional mixing.


“Solution Enhanced Dispersion of Supercritical Solutions” or “SEDS” as used herein involves a spray process for the generation of polymer particles, which are formed when a compressed fluid (e.g. supercritical fluid, preferably supercritical CO2) is used as a diluent to a vehicle in which a polymer dissolved, (one that can dissolve both the polymer and the compressed gas). The mixing of the compressed fluid diluent with the polymer-containing solution may be achieved by encounter of a first stream containing the polymer solution and a second stream containing the diluent compressed fluid, for example, within one co-axial spray nozzle or by the use of multiple spray nozzles or by the use of multiple fluid streams co-entering into a mixing zone. The solvent in the polymer solution may be one compound or a mixture of two or more ingredients and may be or comprise an alcohol (including diols, triols, etc.), ether, amine, ketone, carbonate, or alkanes, or hydrocarbon (aliphatic or aromatic) or may be a mixture of compounds, such as mixtures of alkanes, or mixtures of one or more alkanes in combination with additional compounds such as one or more alcohols. (e.g., from 0 or 0.1 to 5% of a C1 to C15 alcohol, including diols, triols, etc.). See for example U.S. Pat. No. 6,669,785. The solvent may optionally contain a surfactant, as also described in (for example) U.S. Pat. No. 6,669,785.


In one embodiment of the SEDS process, a first stream of fluid comprising a polymer dissolved in a common solvent is co-sprayed with a second stream of compressed fluid. Polymer particles are produced as the second stream acts as a diluent that weakens the solvent in the polymer solution of the first stream. The now combined streams of fluid, along with the polymer particles, flow into a collection vessel. In another embodiment of the SEDS process, a first stream of fluid comprising a drug dissolved in a common solvent is co-sprayed with a second stream of compressed fluid. Drug particles are produced as the second stream acts as a diluent that weakens the solvent in the drug solution of the first stream. The now combined streams of fluid, along with the drug particles, flow out into a collection vessel. Control of particle size, particle size distribution, and morphology is achieved by tailoring the following process variables: temperature, pressure, solvent composition of the first stream, flow-rate of the first stream, flow-rate of the second stream, composition of the second stream (where soluble additives may be added to the compressed gas), and conditions of the capture vessel. Typically the capture vessel contains a fluid phase that is at least five to ten times (5-10×) atmospheric pressure.


“Electrostatically charged” or “electrical potential” or “electrostatic capture” as used herein refers to the collection of the spray-produced particles upon a substrate that has a different electrostatic potential than the sprayed particles. Thus, the substrate is at an attractive electronic potential with respect to the particles exiting, which results in the capture of the particles upon the substrate. i.e. the substrate and particles are oppositely charged, and the particles transport through the fluid medium of the capture vessel onto the surface of the substrate is enhanced via electrostatic attraction. This may be achieved by charging the particles and grounding the substrate or conversely charging the substrate and grounding the particles, or by some other process, which would be easily envisaged by one of skill in the art of electrostatic capture.


“Open vessel” as used herein refers to a vessel open to the outside atmosphere, and thus at substantially the same temperature and pressure as the outside atmosphere.


“Closed vessel” as used herein refers to a vessel sealed from the outside atmosphere, and thus may be at significantly different temperatures and pressures to the outside atmosphere.


EXAMPLES

The following examples are given to enable those skilled in the art to more clearly understand and to practice the present invention. They should not be considered as limiting the scope of the invention, but merely as being illustrative and representative thereof.


Example 1. Dry Powder Rapamycin Coating on an Electrically Charged 316 Stainless Steel Coupon

A 1 cm×2 cm stainless steel metal coupon serving as a target substrate for rapamycin coating was placed in a vessel and attached to a high voltage electrode. The vessel (V), of approximately 1500 cm3 volume, was equipped with two separate nozzles through which rapamycin or polymers could be selectively introduced into the vessel. Both nozzles were grounded. Additionally, the vessel (V) was equipped with a separate port was available for purging the vessel. Upstream of one nozzle (D) was a small pressure vessel (PV) approximately 5 cm3 in volume with three ports to be used as inlets and outlets. Each port was equipped with a valve which could be actuated opened or closed. One port, port (1) used as an inlet, was an addition port for the dry powdered rapamycin. Port (2), also an inlet was used to feed pressurized gas, liquid, or supercritical fluid into PV. Port (3), used as an outlet, was used to connect the pressure vessel (PV) with nozzle (D) contained in the primary vessel (V) with the target coupon. Dry powdered rapamycin obtained from LC Laboratories in a predominantly crystalline solid state, 50 mg milled to an average particle size of approximately 3 microns, was loaded into (PV) through port (1) then port (1) was actuated to the closed position. Gaseous carbon dioxide was then added to (PV) to a pressure of 400 to 600 psig at 20° C. through port (2), then port (2) was closed to the source gas. The metal coupon was then charged to 40 kV using a Glassman Series EL high-voltage power source. Port (3) was then actuated open allowing for the expansion of the pressurized carbon dioxide and rapamycin powder into the vessel (V) while the coupon remained charged. After approximately 60-seconds the voltage was eliminated and the coupon was isolated. Upon visual inspection of the coupon using an optical microscope it was determined that the entire surface area of the coupon, other than a small portion masked by the voltage lead, was covered in a relatively even distribution of powdered material. X-ray diffraction (XRD) confirmed that the powdered material was largely crystalline in nature as deposited on the metal coupon. UV-Vis and FTIR spectroscopy confirmed that the material deposited on the coupon was rapamycin.


Example 2. Dry Powder Rapamycin Coating on a 316-Stainless Steel Coupon with No Electrical Charge

A coupon was coated in an identical fashion to what was described in Example 1. However, no voltage was applied to the coupon throughout the dry powder-coating run. After expansion of the carbon dioxide and the powdered rapamycin into vessel (V), and a period of roughly 60 seconds, the coupon was isolated and evaluated. The coupon was analyzed using an optical microscope and showed some dry powder material on much of the surface of the coupon. However, the coverage of drug on the surface was much lower than in example 1 and there was notably more variability in coverage at different locations on the coupon surface. The total powder coating was estimated to be about ⅓rd the amount determined to be crystalline rapamycin in example 1.


Example 3. Polymer Coating on an Electrically Charged 316-Stainless Steel Coupon Using Rapid Expansion from a Liquefied Gas

A coating apparatus as described in example 1 above was used in the foregoing example. In this example the second nozzle, nozzle (P), was used to feed precipitated polymer particles into vessel (V) to coat a 316-stainless steel coupon. Nozzle (P) was equipped with a heater and controller to minimize heat loss due to the expansion of liquefied gases. Upstream of nozzle (P) was a pressure vessel, (PV2), with approximately 25-cm3 internal volume. The pressure vessel (PV2) was equipped with multiple ports to be used for inlets, outlets, thermocouples, and pressure transducers. Additionally, (PV2) was equipped with a heater and a temperature controller. Each port was connected to the appropriate valves, metering valves, pressure regulators, or plugs to ensure adequate control of material into and out of the pressure vessel (PV2). One outlet from (PV2) was connected to a metering valve through pressure rated tubing which was then connected to nozzle (P) located in vessel (V). In the experiment, 75 mg of polyethylene-co-vinyl acetate (PEVA) obtained from Aldrich Chemical Company with approximately 33-weight percent vinyl acetate and 75 mg of poly(butyl methacrylate) (PBMA) also obtained from Aldrich Chemical Company were added to pressure vessel (PV2). Dichlorofluoromethane, 20.0 grams, was added to the pressure vessel (PV2) through a valve and inlet. Pressure vessel (PV2) was then heated to 40° C. bringing the pressure inside the isolated vessel to approximately 40 psig. Nozzle (P) was heated to 120° C. After sufficient time to dissolve the two polymers in the liquefied gas inside (PV2), the vessel (PV2) was over-pressurized with helium to approximately 200 psig using a source helium tank and a dual stage pressure regulator. See U.S. Pat. No. 6,905,555 for a description of Helium displacement art. A 1-cm×2-cm 316-stainless steel coupon was placed into vessel (V) and attached to an electrical lead. Nozzle (P) was attached to ground. The coupon was charged to 40 kV using a Glassman high-voltage power source at which point the metering valve was opened between (PV2) and nozzle (P) in pressure vessel (PV). Polymer dissolved in liquefied gas and over-pressurized with helium to 200 psig was fed at a constant pressure of 200 psig into vessel (V) maintained at atmospheric pressure through nozzle (P) at an approximate rate of 3.0 cm3/min After approximately 5 seconds, the metering valve was closed discontinuing the polymer-solvent feed. Vessel (V) was purged with gaseous CO2 for 30 seconds to displace chlorofluorocarbon. After approximately 30 seconds, the metering valve was again opened for a period of approximately 5 seconds and then closed. This cycle was repeated about 4 times. After an additional 1-minute the applied voltage to the coupon was discontinued and the coupon was removed from pressure vessel (V). Upon inspection by optical microscope, a polymer coating was evident as evenly distributed on all non-masked surfaces of the coupon. Dissolution of the polymer mixture from the surface of the coupon followed by quantification using standardized quantitative FT-IR methods determined a composition of approximately 1:1 PEVA to PBMA on the coupon.


Example 4. Dual Coating of a Metal Coupon with Crystalline Rapamycin, and 1:1 Mixture of Polyethylene-Co-Vinyl Acetate (PEVA) and Poly(Butyl Methacrylate) (PBMA)

An apparatus described in example ‘1’ and further described in example ‘3’ was used in the foregoing example. In preparation for the coating experiment, 25 mg of crystalline powdered rapamycin with an average particle size of 3-microns was added to (PV) through port (1), then port (1) was closed. Then, (PV) was pressurized to 400-600 psig with gaseous carbon dioxide at 20° C. through port (2), prior to closing port (2). Next, 75 mg of polyethylene-co-vinyl acetate (PEVA) with approximately 33-weight percent vinyl acetate and 75 mg of poly(butyl methacrylate) (PBMA) were added to pressure vessel (PV2). Dichlorofluoromethane, 20.0 grams, was added to the pressure vessel (PV2) through a valve and inlet. Pressure vessel (PV2) was then heated to 40° C. bringing the pressure inside the isolated vessel (PV2) to approximately 40 psig. Nozzle (P) was heated to 120° C. After sufficient time to dissolve the two polymers in the liquefied gas, the vessel was over-pressurized with helium to approximately 200 psig using a source helium tank and a dual stage pressure regulator. A 1-cm×2-cm 316-stainless steel coupon was added to vessel (V) and connected to a high-voltage power lead. Both nozzles (D) and (P) were grounded. To begin, the coupon was charged to 40 kV after which port (3) connecting (PV) containing rapamycin to nozzle (D) was opened allowing expansion of carbon dioxide and ejection of rapamycin into vessel (V) maintained at ambient pressure. After closing port (3) and approximately 60-seconds, the metering valve connecting (PV2) with nozzle (P) inside vessel (V) was opened allowing for expansion of liquefied gas to a gas phase and introduction of precipitated polymer particles into vessel (V) while maintaining vessel (V) at ambient pressure. After approximately 5-seconds at a feed rate of approximately 3 cm3/min., the metering valve was closed while the coupon remained charged. Port (1) was then opened and an additional 25-mg of powdered crystalline rapamycin was added to (PV), and then port (1) was closed. Pressure vessel (PV) was then pressurized with liquid carbon dioxide to 400-600 psig through port (2), after which port (2) was again closed. Maintaining the coupon at an applied voltage of 40 kV, port (3) was again opened to nozzle (D) allowing for the expansion of carbon dioxide to a gas and the ejection of the powdered crystalline drug into the vessel (V). After and additional 60-seconds, the metering valve between (PV2) and nozzle (P) was again opened allowing for the expansion of the liquefied solvent to a gas into vessel (V) and the precipitation of polymer particles also in vessel (V). The sequential addition of drug followed by polymer or polymer followed by drug as described above was repeated for a total of four (4) cycles after which the applied potential was removed from the coupon and the coupon was removed from the vessel. The coupon was then examined using an optical microscope. A consistent coating was visible on all surfaces of the coupon except where the coupon was masked by the electrical lead. The coating appeared conformal but opaque and somewhat granular at high magnification.


Example 5. Dual Coating of a Metal Coupon with Crystalline Rapamycin, and 1:1 Mixture of Polyethylene-Co-Vinyl Acetate (PEVA) and Poly(Butyl Methacrylate) (PBMA) Followed by Supercritical Carbon Dioxide Annealing or Gaseous Carbon Dioxide Annealing

After inspection of the coupon created in example 4, the coated coupon was carefully placed in a pressure vessel that was pressurized with carbon dioxide to a pressure of 4500 psig and at a temperature of 60° C. This CO2 sintering process was done to enhance the physical properties of the film on the coupon. The coupon remained in the vessel under these conditions for approximately 3 hours after which the supercritical CO2 was slowly vented from the pressure vessel and then the coupon was removed and reexamined under an optical microscope. The coating was observed to be conformal, consistent, and semi-transparent as opposed to the opaque coating observed and reported in example 4 without dense carbon dioxide treatment. The coated coupon was then submitted for x-ray diffraction (XRD) analysis to confirm the presence of crystalline rapamycin in the polymer matrix. XRD confirmed the presence of crystalline rapamycin.


Example 6. Dual Coating of a Metal Cardiovascular Stent with Crystalline Rapamycin, and 1:1 Mixture of Polyethylene-Co-Vinyl Acetate (PEVA) and Poly(Butyl Methacrylate) (PBMA)

The apparatus described in examples 1, 3, and 4 above was used in the foregoing example. The metal stent used was a Tristar™ Coronary Stent of a nominal size of 3 mm by 13 mm. The stent was coated in an identical fashion to the coupon described in example 4 above. The stent was coated in an alternating fashion whereby the first coating layer of drug was followed by a thin layer of polymer. These two steps, called a drug/polymer cycle, were repeated 3-times so that the last applied coating layer was polymer. After completion of the coating step, the stent was removed from the vessel (V) and placed in a small pressure vessel where it was exposed to supercritical CO2 as described above in example 4. After this low temperature annealing step, the stent was removed and examined using an optical microscope. The stent was then analyzed using a scanning electron microscope (SEM) equipped with a fast ion bombarding (FIB) device to provide cross-sectional analysis of the coated stent. The SEM micrograph at multiple locations on the stent indicated a completely conformal coating of between 6 and 15-microns in thickness. Evidence of rapamycin crystallites was also apparent in the micrographs.


Example 7. Layered Coating of a Cardiovascular Stent with an Anti-Restenosis Therapeutic and Polymer in Layers to Control Drug Elution Characteristics

A cardiovascular stent is coated using the methods described in examples ‘5’ and ‘6’ above. The stent is coated in such as way that the drug and polymer are in alternating layers. The first application to the bare stent is a thin layer of a non-resorbing polymer, approximately 2-microns thick. The second layer is a therapeutic agent with anti-restenosis indication. Approximately 35 micrograms are added in this second layer. A third layer of polymer is added at approximately 2-microns thick, followed by a fourth drug layer which is composed of about 25 micrograms of the anti-restenosis agent. A fifth polymer layer, approximately 1-micron thick is added to stent, followed by the sixth layer that includes the therapeutic agent of approximately 15-micrograms. Finally, a last polymer layer is added to a thickness of about 2-microns. After the coating procedure, the stent is annealed using carbon dioxide as described in example 4 above. In this example a drug eluting stent (DES) is described with low initial drug “burst” properties by virtue of a “sequestered drug layering” process, not possible in conventional solvent-based coating processes. Additionally, by virtue of a higher concentration of drug at the stent ‘inter-layer’ the elution profile is expected to reach as sustained therapeutic release over a longer period of time.


Example 8. Layered Coating of a Cardiovascular Stent with an Anti-Restenosis Therapeutic and an Anti-Thrombotic Therapeutic in a Polymer Matrix

A cardiovascular stent is coated as described in example 7 above. In this example, after a first polymer layer of approximately 2-microns thick, a drug with anti-thrombotic indication is added in a layer of less than 2-microns in thickness. A third layer consisting of the non-resorbing polymer is added to a thickness of about 4-microns. Next another drug layer is added, a different therapeutic, with an anti-restenosis indication. This layer contains approximately 100 micrograms of the anti-restenosis agent. Finally, a polymer layer approximately 2-microns in thickness is added to the stent. After coating the stent is treated as described in example 4 to anneal the coating using carbon dioxide.


Example 9. Coating of Stents with Rapamycin, Polyethylene-Co-Vinyl Acetate (PEVA) and Polybutyl Methacrylate (PBMA)

Micronized Rapamycin was purchased from LC Laboratories. PBMA (Mw=˜237 k) and PEVA (33% vinyl acetate content) were purchased from Aldrich Chemicals. Two kinds of stents were used: 3 mm TriStar® from Guidant and 6 cell×8-mm, BX Velocity® from Cordis. The stents were coated by dry electrostatic capture followed by supercritical fluid sintering, using 3 stents/coating run and 3 runs/data set. The coating apparatus is represented in FIG. 2. Analysis of the coated stents was performed by multiple techniques on both stents and coupons with relevant control experiments.


In this example a 1:1 ratio of PEVA and PBMA is dissolved in a Dichlorofluoromethane (CCl2FH), which is a compressed gas solvent known to be in the class of “Freon” chemicals. The physical properties of this particular Freon are as follows:


BP=8.9 C


Tc=178.33 C


Pc=751.47 psig


Dc=0.526014 g/cc


A solution was formed by mixing 30 mg of the combined polymers per gram dichlorofluoromethane. The solution was then maintained at 60° C. at vapor pressure (approx 28 psig) until the solution was ready to spray. The solution was then pressurized by adding an immiscible gas to the top of the vessel—typically Helium. Adding Helium compressed the Freon+polymer solution up to 700 (+/−50 psig), which resulted in a compressed fluid. The polymer+Freon solution was then pushed through a nozzle having an inner diameter of 0.005″ by continuous addition of Helium into the vessel. The solvent (dichlorofluoromethane) is rapidly vaporized coming out of the nozzle (which is heated to 120 C), as it's boiling point is significantly below room temperature.


The Drug is deposited by dry powder spray coating. Between 10-30 mg of drug are charged into a small volume of tubing, which is then pressurized with gaseous CO2 to 400 psig. The mixture flows through a nozzle having an inner diameter of 0.187″ into the coating vessel where the stents are held. During electrostatic deposition, the stent is charged and the nozzles are grounded. FIGS. 1 and 2 show the apparatus used for the coating and sintering process.


Example 10. Optical Microscopy Analysis of Rapamycin/PEVA/PBM Coated Stents

The stents produced in example 9 were examined by optical microscopy, at 40× magnification with back and side lighting. This method was used to provide a coarse qualitative representation of coating uniformity and to generally demonstrate the utility of the low-temperature CO2 annealing step. The resulting photos shown in FIG. 3, demonstrate the differences in appearance (a) before and (b) after annealing in dense carbon dioxide at 40° C. Photos of the outside, edge and inside surfaces are presented in FIG. 4(a), prior to sintering, which clearly shows nanoparticle deposition equally on all surfaces of the stent, and 4(b) after sintering, with the film showing a smooth and optically transparent polymer. FIG. 5 shows additional 40× magnified images of Rapamycin/PEVA/PBMA coated stents, showing the outside and inside surfaces, (a) before sintering, further demonstrating the nanoparticle deposition equally on all surfaces of the stent and (b) after sintering, showing a smooth and optically transparent polymer film. FIG. 6 shows a 100× magnified mages of Rapamycin/PEVA/PBMA Coated Stents. Crystalline drug is clearly visible embedded within a highly uniform polymer coating.


Example 11. Scanning Electron Microscopy Analysis of Rapamycin/PEVA/PBM Coated Stents

The stents produced in example 9 were examined by scanning electron microscopy, and the resulting images presented in FIG. 7 at (a) ×30 magnification, (b) ×250 magnification, (c) ×1000 magnification and (d) ×3000 magnification. Clearly the nanoparticles have been sintered to an even and conformal film, with a surface topology of less than 5 microns, and demonstrate clear evidence of embedded crystalline rapamycin.


Cross-sectional (FIB) images were also acquired and are shown in FIG. 8(a) at 7000× and (b) 20000× magnification. An even coating of consistent thickness is visible. Four cross-sectional thicknesses were measured: (1) 10.355 μM, (2) 10.412 μM, (3) 10.043 μM and (4) 10.157 μM, to give an average thickness of 10.242 μM, with only 2% (±0.2 μM) variation.


Example 12. Differential Scanning Calorimetry (DSC) of Rapamycin/PEVA/PBM Coated Stents

The stents produced in example 9 were examined by Differential Scanning Calorimetry (DSC). Control analyses s of PEVA only, PBMA only and Rapamycin only are shown in FIGS. 9(a), (b) and (c) respectively. The DSC of the Rapamycin, PEVA and PBMA coated stent is shown in FIG. 9(d). The rapamycin crystalline melt is clearly visible at 185-200° C. and distinct from those of the polymers.


Example 13. X-Ray Diffraction (XRD) of Rapamycin/PEVA/PBM Coated Stents

The stents produced in example 9 were examined by X-Ray Diffraction (XRD). The control spectrum of micro-ionized Rapamycin powder is shown in FIG. 10(a). The XRD of the Rapamycin, PEVA and PBMA coated, sintered stent is shown in FIG. 10(b), showing that the Rapamycin remains crystalline (˜64%) throughout the coating and sintering process.


Example 14. Confocal Raman Analysis of Rapamycin/PEVA/PBM Coated Stents

The stents produced in example 9 were examined by Confocal Raman Analysis, to provide depth profiling from the coating surface down to the metal stent. FIG. 11(a) shows the Rapamycin depth profile outside circumference (Rapamycin peak at ˜1620) and 11(b) shows the polymer depth profile outside circumference, clearly demonstrating that the drug is distributed throughout polymer coated stents. The highest drug content appears in the center of the polymer coating (˜4 μM from the air surface), which is controllable, via the coating and sintering conditions used. In certain embodiments of the invention, the drug would be close to the air surface of the coating. In other embodiments, the drug would be closer to the metal stent. In other embodiments, more than one drug would be deposited in the coating, wherein one drug would be closer to the air surface and another drug would be closer to the metal surface. In yet other embodiments, the drugs would be distributed together throughout the coating.


Example 15. UV-Vis and FT-IR Analysis of Rapamycin/PEVA/PBM Coated Stents for Quantification of Coating Components

A UV-VIS method was developed and used to quantitatively determine the mass of rapamycin coated onto the stents with poly(ethylene-co-vinyl acetate) (PEVA) and poly(butyl methacrylate) (PBMA). The UV-Vis spectrum of Rapamycin is shown in FIG. 12(a) and a Rapamycin calibration curve was obtained, λ @ 277 nm in ethanol, as shown in FIG. 12(b). Rapamycin was dissolved from the coated stent in ethanol, and the drug concentration and mass calculated. An average mass of 74±11 μg Rapamycin was loaded onto the stents. The results in FIG. 13(a) show a consistent drug coating: (+/−) 15% stent-to-stent, (+/−) 12% run-to-run, (mean concentrations (3 stents each); 4 cell by 8 mm parylene coated).


An FT-IR method was developed and used to quantitatively determine the mass of PEVA and PBMA coated onto stents with rapamycin. The FT-IR spectra of PEVA and PBMA is shown in FIG. 12(c) and calibration curves were obtained using Beer's Law for PEVA λ\,@ ˜1050 cm−1 and PBMA λ@ ˜1285 cm−1, as shown in FIGS. 12(d) and (e), respectively. The polymers were dissolved from the coated stent in methylene chloride, and the polymer concentrations and the masses calculated accordingly. An average mass of 1060±190 μg PEVA and 1110±198 μg PBMA was loaded onto the stents. The results in FIGS. 13(b) and (c) show a consistent polymer coating: (+/−) 18% stent-to-stent, (+/−) 15% run-to-run, (mean concentrations (3 stents each); 4 cell by 8 mm parylene coated).


Example 16. Coating of Stents with Paclitaxel/PEVA/PMBA

3 mm Guidant TriStar® Stents were coated with a Paclitaxel/PEVA/PMBA composite, by processes of the invention, as described herein. The coated stents were examined by optical microscopy, and photos of the outside surface of the stent (a) prior to sintering and (b) after sintering are shown in FIG. 14. FIG. 15(a) represents the UV-Vis calibration curve developed for Paclitaxel, λ @ 228 nm in ethanol, using the methods of example 15, as described above. Rapamycin was dissolved from the coated stent in ethanol, and the drug concentration and mass calculated, to give an average mass of 148±14 μg loaded Rapamycin, as shown in FIG. 15(b).


Example 17. UV-Vis and FT-IR Analysis of Rapamycin/PEVA/PBM Coated Stents for Quantification of Coating Components

The UV-VIS and FT-IR methods, described in example 15, were used to determine the quantities of Rapamycin, PEVA and PBMA respectively, from stents coated with Rapamycin, PEVA and PBMA by processes of the invention, as described herein. The component quantifications are shown in FIG. 16 and calculated; (a) an average mass of 81±3 μg Rapamycin was loaded onto the stents, (b) an average mass of 391±69 μg PEVA and (c) 268±64 μg PBMA was loaded onto the stents.


Example 18. Coating of Stents with Rapamycin or Paclitaxel, Polyethylene-Co-Vinyl Acetate (PEVA) and Polybutyl Methacrylate (PBMA)

A 25 mL stainless steel reservoir is charged with 150.0±0.1 mg of poly(ethylene co-vinyl acetate) (PEVA) and 150.0±0.1 mg of poly(butyl methacrylate) (PBMA) to which is transferred 20.0±0.3 grams of dichlorofluoromethane. The pressure rises in the reservoir to approximately 28 psig. The reservoir is heated to 60° C. after transferring dichlorofluoromethane to the reservoir. The reservoir is then pressurized with helium until the pressure reaches 700±30 psig. Helium acts as a piston to push out the dichlorofluoromethane-polymer solution. The reservoir is isolated from the system by appropriate valving. A second stainless steel reservoir with volume of 15±1 mL is charged with 13 mg of drug compound (rapamycin or Paclitaxel). This reservoir is pressurized to 400±5 psig with carbon dioxide gas. The temperature of the drug reservoir is room temperature. The reservoir is isolated from the system by appropriate valving. A third reservoir is charged with tetrahydrofuran or dichloromethane solvent so that the polymer nozzle can be flushed between polymer sprays. This reservoir is also pressurized with helium to 700 psig and isolated from the system by appropriate valving. The polymer spray nozzle is heated to 120±2° C. while the drug spray nozzle remains at room temperature. Stents are loaded into the stent fixture and attached to a high voltage source via an alligator clamp. The alligator clamp enters the coating chamber via an electrically insulated pass through. Carbon dioxide gas is admitted into the coating vessel at 8 psig for a period of 5 minutes through a third gas flush nozzle to remove air and moisture to eliminate arcing between the nozzles and components held at high potential. After flushing the coating chamber with carbon dioxide gas, a potential of 35 kV is applied to the stents via a high voltage generator. This potential is maintained during each coating step of polymer and drug. The potential is removed when the polymer spray nozzle is flushed with tetrahydrofuran or dichloromethane. Polymer solution is sprayed for 7 secs from the polymer solution reservoir into the coating chamber. The applied potential is turned off and the polymer nozzle is removed from the coating chamber and flushed with solvent for 2 minutes and then flushed with helium gas for approximately one minute until all solvent is removed from the nozzle. The coating chamber is flushed with carbon dioxide gas during the nozzle solvent flush to flush out dichlorofluoromethane gas. The polymer spray nozzle is placed back in the coating chamber and the carbon dioxide gas flush is stopped. A 35 kV potential is applied to the stents and the drug compound is rapidly sprayed into the coating chamber by opening appropriate valving. After one minute of rest time, polymer spray commences for another seven seconds. The process can be repeated with any number of cycles.


While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.


The various analytical methods developed to examine the coated stents and the results they generated are summarized in the table below:














Analytical Method
To Provide
Result







Optical
Visible images of the stents.
Nanoparticles deposited evenly


microscope

on all surfaces of stent



Empirical survey of coating uniformity
Sintering to conformal film (with




visual evidence of crystalline




drug)


SEM
Top-down and cross-sectional images
Very smooth and conformal films



(electron micrographs) at various
at high magnification



magnifications.
10.2 ± 0.3 μm well-sintered films



Gross estimates of coating uniformity
via cross-sectional analysis



and thickness


X-ray diffraction
Quantitative indication of drug
+65% crystalline rapamycin on


(XRD)
morphology in coated films on proxy
proxy samples



substrates


Differential Scanning
Qualitative evidence of crystalline
Demonstrated rapamycin


Calorimetry (DSC)
rapamycin from proxy substrates
crystalline melt (185-200° C.)



(crystalline melt)


Confocal Raman
Compositional data (drug, polymer A,
Drug distributed throughout



Polymer B) at various depths in the film
polymer coated stents



on the coated stents (i.e. surface, 2 μm



deep, 4-μm deep, etc.)


UV-Vis
Quantitative compositional information
74 ± 11 μg drug loaded onto


Spectroscopy
for drug loading on ‘sacrificial’ coated
stents, run-to-run control within



stents, BL method
12% deviation


FT-IR
Quantitative compositional information
1060 ± 190 μg PEVA loaded


spectroscopy
for loading of both polymers on
onto stents



‘sacrificial’ coated stents, BL method
1110 ± 198 μg PBMA loaded




onto stents









Example 19. Preparation of Supercritical Solution Comprising, Polyethylene-Co-Vinyl Acetate (PEVA) and Polybutyl Methacrylate (PBMA) in Isobutylene

75 mg of PEVA and 75 mg of PBMA are placed in a 25 mL view cell. The view cell is heated to 150° C.


Isobutylene is added to a pressure of 3000 psig. Under these conditions, a clear solution is produced.


Example 20. Preparation of Supercritical Solution Comprising Polyethylene-Co-Vinyl Acetate (PEVA) and Polybutyl Methacrylate (PBMA) in Isobutylene

150 mg of PEVA and 150 mg of PBMA are placed in a 25 mL view cell. The view cell is heated to 150° C.


Isobutylene is added to a pressure of 4000 psig. Under these conditions, a clear solution is produced.


Example 21. Preparation of Supercritical Solution Comprising Polyethylene-Co-Vinyl Acetate (PEVA) and Polybutyl Methacrylate (PBMA) in Isobutylene and CO2

75 mg of PEVA and 75 mg of PBMA are placed in a 25 mL view cell and the cell is heated to 150° C.


Isobutylene is added to a pressure of 4000 psig, to produce a clear solution.


10 (v/v %) CO2 is added. The addition of CO2 at this volume percent does not precipitate the dissolved polymer.


Example 22. Preparation of Supercritical Solution Comprising Polyethylene-Co-Vinyl Acetate (PEVA) and Polybutyl Methacrylate (PBMA) in Isobutylene and CO2

150 mg of PEVA and 150 mg of PBMA are placed in a 25 mL view cell and the cell is heated to 150° C.


Isobutylene is added to a pressure of 4000 psig, to produce a clear solution.


10 (v/v %) CO2 is added. The addition of CO2 at this volume percent does not precipitate the dissolved polymer; however addition of CO2 at higher volume fraction leads to polymer precipitation, under these conditions.


Example 23

This example illustrates how the present invention provides a method for optimal design of therapeutic profiles using both anti-restenosis and anti-thrombotic compounds to address both short and long-term safety of drug-eluting stents. This approach which includes multi-drug formulations in biodegradable polymers has the potential to provide improved benefits for both patients and clinicians. The example illustrates an embodiment of the invention to deliver drug-eluting stents by maintaining morphology of therapeutic compounds and providing manufacturing processes that apply discrete and independent therapies within a single, multi-therapy coating under these conditions.


As discussed above, many processes for spray coating stents require that drug and polymer be dissolved in solvent or mutual solvent before spray coating can occur. The present invention provides a method to spray coat stents with drug(s) and polymer(s) in independent steps under conditions that do not require dissolved drug and separates drug and polymer spraying into individual steps. This capability allows discrete placement of drug within a polymer matrix and makes possible placing more than one drug on a single medical device with or without an intervening polymer layer. Discrete deposition and elution of a dual drug coated drug eluting stent using the present invention is summarized below.


Methods: Taxol (98% purity) was purchased from Toronto Research Chemicals. Heparin was purchased from Polysciences, Inc. Polyethylene-co-vinyl acetate (33% w/w vinyl acetate) and Polybutylmethacrylate were purchased from Sigma-Aldrich and used without further purification. All solvents unless otherwise noted were supplied by Sigma-Aldrich and were spectrophotometric grade and used without further purification. Three stents manufactured to requested specifications (Burpee Materials Technology, L.L.C.) were coated simultaneously. Polymer was applied to stents using an electrostatic rapid expansion of a supercritical solution method (RESS) as described above while Heparin and Taxol were applied to stents using a dry powder coating method also described above. Heparin was deposited prior to depositing Taxol with an intervening polymer layer. Heparin was analyzed by UV-Vis spectrophotometry (Ocean Optics) and quantified using the Beer-Lambert relationship using an Azure A assay while Taxol was determined directly from the elution medium at 227 nm. Coated stents were removed from the coating chamber and sintered at 30° C. and approximately 4 bar using the sintering method described above. Taxol drug elution from the polymer matrix was completed by eluting stents in phosphate buffered saline at pH 7.4 with added tween 20 (0.05% w/w) in a thermostatically controlled temperature bath held at 37° C. An aqueous media was used to elute heparin from the polymer matrix. Because of surfactant interference with the azure A assay, heparin elution was quantitatively determined separately from Taxol.


Results: Heparin was loaded on the stent at 70 micrograms and Taxol was loaded on the stent at 78 micrograms. The total polymer mass deposited on the stent was 2.1 milligrams. Heparin and Taxol elution was monitored for 15 days. FIG. 24 shows the cumulative mass of heparin eluted as well as the elution rate. The ability of azure A to continue to bind to heparin suggests that no chemical reaction between heparin and Taxol occurs.


In summary, in certain embodiments, the present invention provides a method for coating drug-eluting stents. Polymer(s) and drug(s) are applied in a controlled, low-temperature, solvent-free process. In one embodiment Rapamycin, PBMA and PEVA are applied to provide a conformal, consistent coating at target Rapamycin loading, in a 1:1 mixture of PBMA:PEVA, at a thickness of ˜10 μM, containing zero residual solvent. The Rapamycin is deposited in crystalline morphology (+50%). The Rapamycin/PEVA/PBMA film is applied using a dry process, wherein the drug and polymer content is highly controllable, and easily adaptable for different drugs, different (resorbable and permanent) polymers, multiple drugs on a single stent, and provides for a high degree of stent-to-stent precision. The absence of traditional solvents during deposition enables control over drug content at variable film depths.


While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims
  • 1. A method of depositing a coating on a substrate comprising: a. providing a substrate;b. depositing at least one polymer layer in dry powder form onto said substrate;c. depositing at least one pharmaceutical layer comprising a pharmaceutical agent onto said substrate without use of a solvent; andd. sintering said at least one polymer layer so as to produce a polymer film fused and adhered to said substrate under conditions that do not substantially modify a morphology of said pharmaceutical agent,wherein said pharmaceutical agent comprises a morphology that is crystalline or semi-crystalline.
  • 2. The method of claim 1, wherein said at least one polymer layer comprises a bioabsorbable polymer.
  • 3. The method of claim 1 wherein said polymer of said at least one polymer layer is selected from PLA, PLGA, PGA and Poly(dioxanone).
  • 4. The method of claim 1 comprising depositing 5 or more layers as follows: a first polymer layer;the first layer comprising said pharmaceutical agent comprising a first pharmaceutical agent;a second polymer layer;the second layer comprising a second pharmaceutical agent; anda third polymer layer.
  • 5. The method of claim 1 comprising depositing 4 or more layers as follows: a first polymer layer;the first layer comprising said first pharmaceutical agent comprising a first pharmaceutical agent;a second polymer layer; andthe second layer comprising a second pharmaceutical agent.
  • 6. The method of claim 1 comprising depositing 4 or more layers as follows: the first layer comprising said pharmaceutical agent comprising a first pharmaceutical agent;a first polymer layer;the second layer comprising a second pharmaceutical agent; anda second polymer layer.
  • 7. The method of claim 1 comprising depositing 3 or more layers as follows: the first layer comprising said pharmaceutical agent comprising a first pharmaceutical agent;a polymer layer; anda second layer comprising a second pharmaceutical agent.
  • 8. The method of claim 1 wherein said first layer and said at least one polymer layer comprising alternate layers of pharmaceutical agent, or pharmaceutical agent and polymer, and layers of polymer without pharmaceutical agent.
  • 9. The method of claim 8, wherein the pharmaceutical agent layers are substantially free of polymer and the polymer layers are substantially free of pharmaceutical agent.
  • 10. The method of claim 1 comprising depositing 5, 10, 20, 50, or 100 layers.
  • 11. The method of claim 4 wherein said first pharmaceutical agent has an elution profile that is slower than the elution profile of said second pharmaceutical agent.
  • 12. The method of claim 11 wherein the second pharmaceutical agent achieves 100% elution in about 5 days to about 20 days and the first pharmaceutical agent achieves 100% elution in about 120 days to about 180 days.
  • 13. The method of claim 4, wherein said first pharmaceutical agent is anti-thrombogenic agent and said second pharmaceutical agent is an anti-restenotic agent.
  • 14. The method of claim 4, wherein said first pharmaceutical agent is heparin and said second pharmaceutical agent is taxol or a macrolide immunosuppressive (limus) drug.
  • 15. The method of claim 2, wherein said bioabsorbable polymer is selected from PGA poly(glycolide), LPLA poly(l-lactide), DLPLA poly(dl-lactide), PCL poly(e-caprolactone) PDO, poly(dioxolane) PGA-TMC, 85/15 DLPLG p(dl-lactide-co-glycolide), 75/25 DLPLG, 65/35 DLPLG, 50/50 DLPLG, TMC poly(trimethylcarbonate), and p(CPP:SA) poly(1,3-bis-p-(carboxyphenoxy)propane-co-sebacic acid).
  • 16. The method of claim 1, wherein said pharmaceutical agent comprises a macrolide immunosuppressive (limus) drug.
  • 17. The method of claim 16, wherein the macrolide immunosuppressive drug comprises one or more of rapamycin, 40-O-(2-Hydroxyethyl)rapamycin (everolimus), 40-O-Benzyl-rapamycin, 40-O-(4′-Hydroxymethyl)benzyl-rapamycin, 40-O-[4′-(1,2-Dihydroxyethyl)]benzyl-rapamycin, 40-O-Allyl-rapamycin, 40-O-[3′-(2,2-Dimethyl-1,3-dioxolan-4(S)-yl)-prop-2′-en-1′-yl]-rapamycin, (2′:E,4′S)-40-O-(4′,5′-Dihydroxypent-2′-en-1′-yl)-rapamycin, 40-O-(2-Hydroxy)ethoxycarbonylmethyl-rapamycin, 40-O-(3-Hydroxy)propyl-rapamycin, 40-O-(6-Hydroxy)hexyl-rapamycin, 40-O-[2-(2-Hydroxy) ethoxy]ethyl-rapamycin, 40-O-[(3S)-2,2-Dimethyldioxolan-3-yl]methyl-rapamycin, 40-O-[(2S)-2,3-Dihydroxyprop-1-yl]-rapamycin, 40-O-(2-Acetoxy)ethyl-rapamycin, 40-O-(2-Nicotinoyloxy)ethyl-rapamycin, 40-O-[2-(N-Morpholino)acetoxy]ethyl-rapamycin, 40-O-(2-N-Imidazolylacetoxy)ethyl-rapamycin, 40-O-[2-(N-Methyl-N′-piperazinyl)acetoxy]ethyl-rapamycin, 39-O-Desmethyl-39,40-O,O-ethylene-rapamycin, (26R)-26-Dihydro-40-O-(2-hydroxy)ethyl-rapamycin, 28-O-Methyl-rapamycin, 40-O-(2-Aminoethyl)-rapamycin, 40-O-(2-Acetaminoethyl)-rapamycin, 40-O-(2-Nicotinamidoethyl)-rapamycin, 40-O-(2-(N-Methyl-imidazo-2′-ylcarbethoxamido)ethyl)-rapamycin, 40-O-(2-Ethoxycarbonylaminoethyl)-rapamycin, 40-O-(2-Tolylsulfonamidoethyl)-rapamycin, 40-O-[2-(4′,5′-Dicarboethoxy-1′,2′,3′-triazol-1′-yl)-ethyl]-rapamycin, 42-Epi-(tetrazolyl) rapamycin (tacrolimus), 42-[3-hydroxy-2-(hydroxymethyl)-2-methylpropanoate]rapamycin (temsirolimus), and 40-epi-(N1-tetrazolyl)-rapamycin (zotarolimus).
  • 18. The method of claim 16, wherein said macrolide immunosuppressive drug is at least 50% crystalline.
  • 19. The method of claim 1, wherein said depositing of said at least one polymer layer comprises depositing polymer particles on said substrate by an RESS process.
  • 20. The method of claim 1, wherein the substrate is a biomedical implant selected from the group consisting of a stent, electrode, catheter, lead, implantable pacemaker or cardioverter housing, joint, screw, rod, ophthalmic implant, prosthetic, and shunt.
  • 21. A coated substrate comprising a. a substrate; andb. at least one polymer layer;c. a pharmaceutical layer comprising at least one pharmaceutical agent;wherein said at least one polymer layer has a thickness of from about 1 to 100 μm and comprises a sintered layer in which the morphology of said pharmaceutical agent in said coating has not been substantially modified and said first pharmaceutical agent is crystalline or semi-crystalline, and wherein said polymer layer is discontinuous thereby providing at least a portion of said polymer layer comprising said pharmaceutical agents.
  • 22. The substrate of claim 21, wherein said at least one polymer layer comprises a bioabsorbable polymer.
  • 23. The substrate of claim 21 wherein said polymer of said at least one polymer layer is selected from PLA, PLGA, PGA and Poly(dioxanone).
  • 24. The substrate of claim 21 comprising 5 or more layers as follows: a first polymer layera first pharmaceutical layer comprising said at least one pharmaceutical agenta second polymer layera second pharmaceutical layer comprising a second pharmaceutical agent; anda third polymer layer.
  • 25. The substrate of claim 21 comprising 4 or more layers as follows: a first polymer layera first pharmaceutical layer comprising said at least one pharmaceutical agenta second polymer layer; anda second pharmaceutical layer comprising a second pharmaceutical agent.
  • 26. The substrate of claim 21 comprising 4 or more layers as follows: the first pharmaceutical layer comprising a first pharmaceutical agenta first polymer layera second pharmaceutical layer comprising a second pharmaceutical agent; anda second polymer layer.
  • 27. The substrate of claim 21 comprising 3 or more layers as follows: a first pharmaceutical layer comprising said first pharmaceutical agenta polymer layer; anda second pharmaceutical layer comprising a second pharmaceutical agent.
  • 28. The substrate of claim 21 wherein said pharmaceutical layer and said at least one polymer layer comprises alternate layers of pharmaceutical agent, or pharmaceutical agent and polymer, and layers of polymer without pharmaceutical agent.
  • 29. The substrate of claim 27, wherein pharmaceutical is substantially free of polymer and said at least one polymer layer is substantially free of pharmaceutical agent.
  • 30. The substrate of claim 21 comprising depositing 5, 10, 20, 50, or 100 layers.
  • 31. The substrate of claim 24 wherein said first pharmaceutical layer has an elution profile that is slower than the elution profile of said second pharmaceutical agent.
  • 32. The substrate of claim 31 wherein the second pharmaceutical agent achieves 100% elution in about 5 days to about 20 days and the first pharmaceutical agent achieves 100% elution in about 120 days to about 180 days.
  • 33. The substrate of claim 24, wherein said first pharmaceutical agent is anti-thrombogenic agent and said second pharmaceutical agent is an anti-restenotic agent.
  • 34. The substrate of claim 24, wherein said first pharmaceutical agent is heparin and said second agent is taxol or a macrolide immunosuppressive (limus) drug.
  • 35. The substrate of claim 22, wherein said bioabsorbable polymer is selected from PGA poly(glycolide), LPLA poly(l-lactide), DLPLA poly(dl-lactide), PCL poly(e-caprolactone) PDO, poly(dioxolane) PGA-TMC, 85/15 DLPLG p(dl-lactide-co-glycolide), 75/25 DLPLG, 65/35 DLPLG, 50/50 DLPLG, TMC poly(trimethylcarbonate), and p(CPP:SA) poly(1,3-bis-p-(carboxyphenoxy)propane-co-sebacic acid).
  • 36. The substrate of claim 24, wherein at least one of said pharmaceutical agents comprise a macrolide immunosuppressive (limus) drug.
  • 37. The substrate of claim 36, wherein the macrolide immunosuppressive drug comprises one or more of rapamycin, 40-O-(2-Hydroxyethyl)rapamycin (everolimus), 40-O-Benzyl-rapamycin, 40-O-(4′-Hydroxymethyl)benzyl-rapamycin, 40-O-[4′-(1,2-Dihydroxyethyl)]benzyl-rapamycin, 40-O-Allyl-rapamycin, 40-O-[3′-(2,2-Dimethyl-1,3-dioxolan-4(S)-yl)-prop-2′-en-1′-yl]-rapamycin, (2′:E,4′S)-40-O-(4′,5′-Dihydroxypent-2′-en-1′-yl)-rapamycin, 40-O-(2-Hydroxy)ethoxycarbonylmethyl-rapamycin, 40-O-(3-Hydroxy)propyl-rapamycin, 40-O-(6-Hydroxy)hexyl-rapamycin, 40-O-[2-(2-Hydroxy)ethoxy]ethyl-rapamycin,40-O-[(3S)-2,2-Dimethyldioxolan-3-yl]methyl-rapamycin, 40-O-[(2S)-2,3-Dihydroxyprop-1-yl]-rapamycin, 40-O-(2-Acetoxy)ethyl-rapamycin, 40-O-(2-Nicotinoyloxy)ethyl-rapamycin, 40-O-[2-(N-Morpholino)acetoxy]ethyl-rapamycin, 40-O-(2-N-Imidazolylacetoxy)ethyl-rapamycin, 40-O-[2-(N-Methyl-N′-piperazinyl)acetoxy]ethyl-rapamycin, 39-O-Desmethyl-39,40-O,O-ethylene-rapamycin, (26R)-26-Dihydro-40-O-(2-hydroxy)ethyl-rapamycin, 28-O-Methyl-rapamycin, 40-O-(2-Aminoethyl)-rapamycin, 40-O-(2-Acetaminoethyl)-rapamycin, 40-O-(2-Nicotinamidoethyl)-rapamycin, 40-O-(2-(N-Methyl-imidazo-2′-ylcarbethoxamido)ethyl)-rapamycin, 40-O-(2-Ethoxycarbonylaminoethyl)-rapamycin, 40-O-(2-Tolylsulfonamidoethyl)-rapamycin, 40-O-[2-(4′,5′-Dicarboethoxy-1′,2′,3′-triazol-1′-yl)-ethyl]-rapamycin, 42-Epi-(tetrazolyl)rapamycin (tacrolimus), 42-[3-hydroxy-2-(hydroxymethyl)-2-methylpropanoate]rapamycin (temsirolimus), and 40-epi-(N1-tetrazolyl)-rapamycin (zotarolimus).
  • 38. The substrate of claim 36, wherein the macrolide immunosuppressive drug is at least 50% crystalline.
  • 39. The substrate of claim 21, wherein the substrate is a biomedical implant selected from the group consisting of a stent, electrode, catheter, lead, implantable pacemaker or cardioverter housing, joint, screw, rod, ophthalmic implant, prosthetic, and shunt.
  • 40. The method of claim 1 wherein said depositing of said at least one polymer layer and said depositing of said at least one pharmaceutical layer are carried out simultaneously.
  • 41. The method of claim 1 wherein said depositing of said at least one polymer layer and said depositing of said at least one pharmaceutical layer are carried out in succession.
CROSS-REFERENCE

The present application is a continuation of U.S. patent application Ser. No. 14/473,741, filed on Aug. 29, 2014, the disclosure of which is hereby incorporated herein by reference, which claims the benefit of U.S. application Ser. No. 12/298,459, filed Mar. 16, 2009, which was filed pursuant to 35 U.S.C. §371 as a United States National Phase Application of International Application No. PCT/US2007/010227, filed Apr. 26, 2007, which claims the benefit of U.S. Provisional Application Nos. 60/912,394 filed Apr. 17, 2007; 60/745,731 filed Apr. 26, 2006; and 60/745,733 filed Apr. 26, 2006, each of which are incorporated herein by reference in their entirety.

US Referenced Citations (490)
Number Name Date Kind
3087860 Endicott et al. Apr 1963 A
3123077 Alcamo Mar 1964 A
3457280 Schmitt et al. Jul 1969 A
3597449 Deprospero et al. Aug 1971 A
3737337 Schnoring et al. Jun 1973 A
3773919 Boswell et al. Nov 1973 A
3929992 Sehgal et al. Dec 1975 A
4000137 Dvonch et al. Dec 1976 A
4188373 Krezanoski Feb 1980 A
4285987 Ayer et al. Aug 1981 A
4326532 Hammar Apr 1982 A
4336381 Nagata et al. Jun 1982 A
4389330 Tice et al. Jun 1983 A
4474572 McNaughton et al. Oct 1984 A
4474751 Haslam et al. Oct 1984 A
4478822 Haslam et al. Oct 1984 A
4530840 Tice et al. Jul 1985 A
4582731 Smith Apr 1986 A
4606347 Fogarty et al. Aug 1986 A
4617751 Johansson Oct 1986 A
4655771 Wallsten Apr 1987 A
4675189 Kent et al. Jun 1987 A
4733665 Palmaz Mar 1988 A
4734227 Smith Mar 1988 A
4734451 Smith Mar 1988 A
4758435 Schaaf Jul 1988 A
4762593 Youngner Aug 1988 A
4931037 Wetterman Jun 1990 A
4950239 Gahara et al. Aug 1990 A
4985625 Hurst Jan 1991 A
5000519 Moore Mar 1991 A
5090419 Palestrant Feb 1992 A
5096848 Kawamura Mar 1992 A
5102417 Palmaz Apr 1992 A
5104404 Wolff Apr 1992 A
5106650 Hoy et al. Apr 1992 A
5125570 Jones Jun 1992 A
5158986 Cha et al. Oct 1992 A
5185776 Townsend Feb 1993 A
5195969 Wang et al. Mar 1993 A
5243023 Dezem Sep 1993 A
5270086 Hamlin Dec 1993 A
5288711 Mitchell et al. Feb 1994 A
5320634 Vigil et al. Jun 1994 A
5324049 Mistrater et al. Jun 1994 A
5340614 Perman et al. Aug 1994 A
5342621 Eury Aug 1994 A
5350361 Tsukashima et al. Sep 1994 A
5350627 Nemphos et al. Sep 1994 A
5356433 Rowland et al. Oct 1994 A
5360403 Mische Nov 1994 A
5362718 Skotnicki et al. Nov 1994 A
5366504 Andersen et al. Nov 1994 A
5368045 Clement et al. Nov 1994 A
5372676 Lowe Dec 1994 A
5385776 Maxfield et al. Jan 1995 A
5387313 Thoms Feb 1995 A
5403347 Roby et al. Apr 1995 A
5470603 Staniforth et al. Nov 1995 A
5494620 Liu et al. Feb 1996 A
5500180 Anderson et al. Mar 1996 A
5545208 Wolff et al. Aug 1996 A
5556383 Wang et al. Sep 1996 A
5562922 Lambert Oct 1996 A
5569463 Helmus et al. Oct 1996 A
5570537 Black et al. Nov 1996 A
5578709 Woiszwillo Nov 1996 A
5599576 Opolski Feb 1997 A
5607442 Fischell et al. Mar 1997 A
5609629 Fearnot et al. Mar 1997 A
5626611 Liu et al. May 1997 A
5626862 Brem et al. May 1997 A
5632772 Alcime et al. May 1997 A
5669932 Fischell et al. Sep 1997 A
5674242 Phan et al. Oct 1997 A
5725570 Heath Mar 1998 A
5733303 Israel et al. Mar 1998 A
5800511 Mayer Sep 1998 A
5807404 Richter Sep 1998 A
5811032 Kawai et al. Sep 1998 A
5824049 Ragheb et al. Oct 1998 A
5837313 Ding et al. Nov 1998 A
5843120 Israel et al. Dec 1998 A
5871436 Eury Feb 1999 A
5873904 Ragheb Feb 1999 A
5876426 Kume et al. Mar 1999 A
5913895 Burpee et al. Jun 1999 A
5924631 Rodrigues et al. Jul 1999 A
5948020 Yoon et al. Sep 1999 A
5957975 Lafont et al. Sep 1999 A
5981568 Kunz et al. Nov 1999 A
5981719 Woiszwillo et al. Nov 1999 A
6013855 McPherson et al. Jan 2000 A
6036978 Gombotz et al. Mar 2000 A
6039721 Johnson et al. Mar 2000 A
6068656 Von Oepen May 2000 A
6071308 Ballou et al. Jun 2000 A
6077880 Castillo et al. Jun 2000 A
6090925 Woiszwillo et al. Jul 2000 A
6129755 Mathis et al. Oct 2000 A
6143037 Goldstein et al. Nov 2000 A
6143314 Chandrashekar et al. Nov 2000 A
6146356 Wang et al. Nov 2000 A
6146404 Kim et al. Nov 2000 A
6153252 Hossainy et al. Nov 2000 A
6171327 Daniel et al. Jan 2001 B1
6190699 Luzzi et al. Feb 2001 B1
6193744 Ehr et al. Feb 2001 B1
6206914 Soykan et al. Mar 2001 B1
6217608 Penn et al. Apr 2001 B1
6231599 Ley May 2001 B1
6231600 Zhong May 2001 B1
6245104 Alt Jun 2001 B1
6248127 Shah et al. Jun 2001 B1
6248129 Froix Jun 2001 B1
6251980 Lan et al. Jun 2001 B1
6268053 Woiszwillo et al. Jul 2001 B1
6273913 Wright et al. Aug 2001 B1
6284758 Egi et al. Sep 2001 B1
6299635 Frantzen Oct 2001 B1
6309669 Setterstrom et al. Oct 2001 B1
6319541 Pletcher et al. Nov 2001 B1
6325821 Gaschino et al. Dec 2001 B1
6336934 Gilson et al. Jan 2002 B1
6342062 Suon et al. Jan 2002 B1
6344055 Shukov Feb 2002 B1
6355691 Goodman Mar 2002 B1
6358556 Ding et al. Mar 2002 B1
6361819 Tedeschi et al. Mar 2002 B1
6362718 Patrick et al. Mar 2002 B1
6364903 Tseng et al. Apr 2002 B2
6368658 Schwarz et al. Apr 2002 B1
6372246 Wei et al. Apr 2002 B1
6387121 Alt May 2002 B1
6409716 Sahatjian et al. Jun 2002 B1
6414050 Howdle et al. Jul 2002 B1
6416779 D'Augustine et al. Jul 2002 B1
6448315 Lidgren et al. Sep 2002 B1
6458387 Scott et al. Oct 2002 B1
6461380 Cox Oct 2002 B1
6461644 Jackson et al. Oct 2002 B1
6488703 Kveen et al. Dec 2002 B1
6495163 Jordan Dec 2002 B1
6497729 Moussy et al. Dec 2002 B1
6506213 Mandel et al. Jan 2003 B1
6517860 Roser et al. Feb 2003 B1
6521258 Mandel et al. Feb 2003 B1
6524698 Schmoock Feb 2003 B1
6530951 Bates et al. Mar 2003 B1
6537310 Palmaz et al. Mar 2003 B1
6541033 Shah Apr 2003 B1
6572813 Zhang et al. Jun 2003 B1
6602281 Klein Aug 2003 B1
6610013 Fenster et al. Aug 2003 B1
6627246 Mehta et al. Sep 2003 B2
6649627 Cecchi et al. Nov 2003 B1
6660176 Tepper et al. Dec 2003 B2
6669785 DeYoung et al. Dec 2003 B2
6669980 Hansen Dec 2003 B2
6670407 Howdle et al. Dec 2003 B2
6682757 Wright Jan 2004 B1
6706283 Appel et al. Mar 2004 B1
6710059 Labrie et al. Mar 2004 B1
6720003 Chen et al. Apr 2004 B2
6723913 Barbetta Apr 2004 B1
6726712 Raeder-Devens et al. Apr 2004 B1
6736996 Carbonell et al. May 2004 B1
6743505 Antal et al. Jun 2004 B2
6749902 Yonker et al. Jun 2004 B2
6755871 Damaso et al. Jun 2004 B2
6756084 Fulton et al. Jun 2004 B2
6767558 Wang Jul 2004 B2
6780475 Fulton et al. Aug 2004 B2
6794902 Becker et al. Sep 2004 B2
6800663 Asgarzadeh et al. Oct 2004 B2
6815218 Jacobson et al. Nov 2004 B1
6821549 Jayaraman Nov 2004 B2
6837611 Kuo Jan 2005 B2
6838089 Carlsson et al. Jan 2005 B1
6838528 Zhao Jan 2005 B2
6858598 McKearn et al. Feb 2005 B1
6860123 Uhlin Mar 2005 B1
6868123 Bellas et al. Mar 2005 B2
6884377 Burnham et al. Apr 2005 B1
6884823 Pierick et al. Apr 2005 B1
6897205 Beckert et al. May 2005 B2
6905555 DeYoung et al. Jun 2005 B2
6908624 Hossainy et al. Jun 2005 B2
6916800 McKearn et al. Jul 2005 B2
6923979 Fotland et al. Aug 2005 B2
6936270 Watson et al. Aug 2005 B2
6939569 Green et al. Sep 2005 B1
6973718 Sheppard, Jr. et al. Dec 2005 B2
7056591 Pacetti et al. Jun 2006 B1
7094256 Shah et al. Aug 2006 B1
7148201 Stern et al. Dec 2006 B2
7152452 Kokish Dec 2006 B2
7160592 Rypacek et al. Jan 2007 B2
7163715 Kramer Jan 2007 B1
7169404 Hossainy et al. Jan 2007 B2
7171255 Holupka et al. Jan 2007 B2
7201750 Eggers et al. Apr 2007 B1
7201940 Kramer Apr 2007 B1
7229837 Chen Jun 2007 B2
7278174 Villalobos Oct 2007 B2
7279174 Pacetti et al. Oct 2007 B2
7282020 Kaplan Oct 2007 B2
7308748 Kokish Dec 2007 B2
7323454 De Nijs et al. Jan 2008 B2
7326734 Zi et al. Feb 2008 B2
7329383 Stinson Feb 2008 B2
7378105 Burke et al. May 2008 B2
7419696 Berg et al. Sep 2008 B2
7429378 Serhan et al. Sep 2008 B2
7444162 Hassan Oct 2008 B2
7455658 Wang Nov 2008 B2
7455688 Furst et al. Nov 2008 B2
7456151 Li et al. Nov 2008 B2
7462593 Cuttitta et al. Dec 2008 B2
7485113 Varner et al. Feb 2009 B2
7498042 Igaki et al. Mar 2009 B2
7524865 D'Amato et al. Apr 2009 B2
7537610 Reiss May 2009 B2
7537785 Loscalzo et al. May 2009 B2
7553827 Attawia et al. Jun 2009 B2
7713538 Lewis et al. May 2010 B2
7727275 Betts et al. Jun 2010 B2
7745566 Chattopadhyay et al. Jun 2010 B2
7763277 Canham et al. Jul 2010 B1
7771468 Whitbourne et al. Aug 2010 B2
7837726 Von Oepen et al. Nov 2010 B2
7842312 Burgermeister et al. Nov 2010 B2
7919108 Reyes et al. Apr 2011 B2
7955383 Krivoruchko et al. Jun 2011 B2
7967855 Furst et al. Jun 2011 B2
7972661 Pui et al. Jul 2011 B2
8070796 Furst et al. Dec 2011 B2
8295565 Gu et al. Oct 2012 B2
8298565 Taylor et al. Oct 2012 B2
8377356 Huang et al. Feb 2013 B2
8535372 Fox et al. Sep 2013 B1
8709071 Huang et al. Apr 2014 B1
8753659 Lewis et al. Jun 2014 B2
8753709 Hossainy Jun 2014 B2
8758429 Taylor et al. Jun 2014 B2
8795762 Fulton et al. Aug 2014 B2
8834913 Shaw et al. Sep 2014 B2
8852625 DeYoung et al. Oct 2014 B2
8900651 McClain et al. Dec 2014 B2
20010026804 Boutignon Oct 2001 A1
20010034336 Shah et al. Oct 2001 A1
20010044629 Stinson Nov 2001 A1
20010049551 Tseng et al. Dec 2001 A1
20020007209 Scheerder et al. Jan 2002 A1
20020051485 Bottomley May 2002 A1
20020051845 Mehta et al. May 2002 A1
20020082680 Shanley et al. Jun 2002 A1
20020091433 Ding et al. Jul 2002 A1
20020099332 Slepian et al. Jul 2002 A1
20020125860 Schworm et al. Sep 2002 A1
20020133072 Wang et al. Sep 2002 A1
20020144757 Craig et al. Oct 2002 A1
20030001830 Wampler et al. Jan 2003 A1
20030031699 Van Antwerp Feb 2003 A1
20030077200 Craig et al. Apr 2003 A1
20030088307 Shulze et al. May 2003 A1
20030125800 Shulze et al. Jul 2003 A1
20030143315 Pui et al. Jul 2003 A1
20030170305 O'Neil et al. Sep 2003 A1
20030180376 Dalal et al. Sep 2003 A1
20030185964 Weber et al. Oct 2003 A1
20030204238 Tedeschi Oct 2003 A1
20030222017 Fulton et al. Dec 2003 A1
20030222018 Yonker et al. Dec 2003 A1
20030232014 Burke et al. Dec 2003 A1
20040013792 Epstein et al. Jan 2004 A1
20040018228 Fischell et al. Jan 2004 A1
20040022400 Magrath Feb 2004 A1
20040022853 Ashton et al. Feb 2004 A1
20040044397 Stinson Mar 2004 A1
20040059290 Palasis Mar 2004 A1
20040102758 Davila et al. May 2004 A1
20040106982 Jalisi Jun 2004 A1
20040122205 Nathan Jun 2004 A1
20040126542 Fujiwara et al. Jul 2004 A1
20040143317 Stinson et al. Jul 2004 A1
20040144317 Chuman et al. Jul 2004 A1
20040147904 Hung et al. Jul 2004 A1
20040157789 Geall Aug 2004 A1
20040170685 Carpenter et al. Sep 2004 A1
20040193177 Houghton et al. Sep 2004 A1
20040193262 Shadduck Sep 2004 A1
20040220660 Shanley et al. Nov 2004 A1
20040224001 Pacetti et al. Nov 2004 A1
20040236416 Falotico Nov 2004 A1
20040260000 Chaiko Dec 2004 A1
20050003074 Brown et al. Jan 2005 A1
20050004661 Lewis et al. Jan 2005 A1
20050010275 Sahatjian et al. Jan 2005 A1
20050015046 Weber et al. Jan 2005 A1
20050019747 Anderson et al. Jan 2005 A1
20050033414 Zhang et al. Feb 2005 A1
20050038498 Dubrow et al. Feb 2005 A1
20050048121 East et al. Mar 2005 A1
20050049694 Neary Mar 2005 A1
20050060028 Horres et al. Mar 2005 A1
20050069630 Fox et al. Mar 2005 A1
20050070989 Lye et al. Mar 2005 A1
20050070990 Stinson Mar 2005 A1
20050074479 Weber et al. Apr 2005 A1
20050075714 Cheng et al. Apr 2005 A1
20050079199 Heruth et al. Apr 2005 A1
20050079274 Palasis et al. Apr 2005 A1
20050084533 Howdle et al. Apr 2005 A1
20050131513 Myers Jun 2005 A1
20050147734 Seppala et al. Jul 2005 A1
20050166841 Robida Aug 2005 A1
20050175772 Worsham et al. Aug 2005 A1
20050177223 Palmaz Aug 2005 A1
20050191491 Wang et al. Sep 2005 A1
20050196424 Chappa Sep 2005 A1
20050208102 Schultz Sep 2005 A1
20050209244 Prescott et al. Sep 2005 A1
20050216075 Wang et al. Sep 2005 A1
20050238829 Motherwell et al. Oct 2005 A1
20050255327 Chaney et al. Nov 2005 A1
20050260186 Bookbinder et al. Nov 2005 A1
20050268573 Yan Dec 2005 A1
20050288481 DesNoyer et al. Dec 2005 A1
20050288629 Kunis Dec 2005 A1
20060001011 Wilson et al. Jan 2006 A1
20060002974 Pacetti et al. Jan 2006 A1
20060020325 Burgermeister et al. Jan 2006 A1
20060030652 Adams et al. Feb 2006 A1
20060045901 Weber Mar 2006 A1
20060073329 Boyce et al. Apr 2006 A1
20060089705 Ding et al. Apr 2006 A1
20060093771 Rypacek et al. May 2006 A1
20060094744 Maryanoff et al. May 2006 A1
20060106455 Furst et al. May 2006 A1
20060116755 Stinson Jun 2006 A1
20060121080 Lye et al. Jun 2006 A1
20060121089 Michal et al. Jun 2006 A1
20060134168 Chappa et al. Jun 2006 A1
20060134211 Lien et al. Jun 2006 A1
20060136041 Schmid et al. Jun 2006 A1
20060147698 Carroll et al. Jul 2006 A1
20060153729 Stinson et al. Jul 2006 A1
20060160455 Sugyo et al. Jul 2006 A1
20060188547 Bezwada Aug 2006 A1
20060193886 Owens et al. Aug 2006 A1
20060193890 Owens et al. Aug 2006 A1
20060198868 DeWitt et al. Sep 2006 A1
20060210638 Liversidge et al. Sep 2006 A1
20060216324 Stucke et al. Sep 2006 A1
20060222756 Davila et al. Oct 2006 A1
20060228415 Oberegger et al. Oct 2006 A1
20060228453 Cromack et al. Oct 2006 A1
20060235506 Ta et al. Oct 2006 A1
20060276877 Owens et al. Dec 2006 A1
20060287611 Fleming Dec 2006 A1
20070009564 McClain et al. Jan 2007 A1
20070009664 Fallais et al. Jan 2007 A1
20070026042 Narayanan Feb 2007 A1
20070032864 Furst et al. Feb 2007 A1
20070038227 Massicotte et al. Feb 2007 A1
20070038289 Nishide et al. Feb 2007 A1
20070059350 Kennedy et al. Mar 2007 A1
20070065478 Hossainy Mar 2007 A1
20070110888 Radhakrishnan et al. May 2007 A1
20070123973 Roth et al. May 2007 A1
20070123977 Cottone et al. May 2007 A1
20070128274 Zhu et al. Jun 2007 A1
20070148251 Hossainy et al. Jun 2007 A1
20070154513 Atanasoska et al. Jul 2007 A1
20070154554 Burgermeister et al. Jul 2007 A1
20070196242 Boozer et al. Aug 2007 A1
20070196423 Ruane et al. Aug 2007 A1
20070198081 Castro et al. Aug 2007 A1
20070200268 Dave Aug 2007 A1
20070203569 Burgermeister et al. Aug 2007 A1
20070219579 Paul Sep 2007 A1
20070225795 Granada et al. Sep 2007 A1
20070259017 Francis Nov 2007 A1
20070280992 Margaron et al. Dec 2007 A1
20080030066 Mercier et al. Feb 2008 A1
20080051866 Chen et al. Feb 2008 A1
20080065192 Berglund Mar 2008 A1
20080071347 Cambronne Mar 2008 A1
20080071358 Weber et al. Mar 2008 A1
20080071359 Thornton et al. Mar 2008 A1
20080075753 Chappa Mar 2008 A1
20080077232 Nishide Mar 2008 A1
20080085880 Viswanath et al. Apr 2008 A1
20080095919 McClain et al. Apr 2008 A1
20080097575 Cottone Apr 2008 A1
20080097591 Savage et al. Apr 2008 A1
20080098178 Veazey et al. Apr 2008 A1
20080107702 Jennissen May 2008 A1
20080118543 Pacetti et al. May 2008 A1
20080124372 Hossainy et al. May 2008 A1
20080138375 Yan et al. Jun 2008 A1
20080206304 Lindquist et al. Aug 2008 A1
20080213464 O'Connor Sep 2008 A1
20080233267 Berglund Sep 2008 A1
20080255510 Wang Oct 2008 A1
20080269449 Chattopadhyay et al. Oct 2008 A1
20080292776 Dias et al. Nov 2008 A1
20080300669 Hossainy Dec 2008 A1
20080300689 Mc Kinnon et al. Dec 2008 A1
20090043379 Prescott Feb 2009 A1
20090062909 Taylor et al. Mar 2009 A1
20090068266 Raheja et al. Mar 2009 A1
20090076446 Dubuclet, IV et al. Mar 2009 A1
20090082855 Borges et al. Mar 2009 A1
20090098178 Hofmann et al. Apr 2009 A1
20090105687 Deckman et al. Apr 2009 A1
20090105809 Lee et al. Apr 2009 A1
20090110711 Trollsas et al. Apr 2009 A1
20090111787 Lim et al. Apr 2009 A1
20090123515 Taylor et al. May 2009 A1
20090186069 DeYoung et al. Jul 2009 A1
20090202609 Keough et al. Aug 2009 A1
20090216317 Cromack et al. Aug 2009 A1
20090227949 Knapp et al. Sep 2009 A1
20090231578 Ling et al. Sep 2009 A1
20090263460 McDonald Oct 2009 A1
20090285974 Kerrigan et al. Nov 2009 A1
20090292351 McClain et al. Nov 2009 A1
20090292776 Nesbitt et al. Nov 2009 A1
20090297578 Trollsas et al. Dec 2009 A1
20090300689 Conte et al. Dec 2009 A1
20100000328 Mahmoud Jan 2010 A1
20100006358 Ishikawa Jan 2010 A1
20100015200 McClain et al. Jan 2010 A1
20100030261 McClain Feb 2010 A1
20100042206 Yadav et al. Feb 2010 A1
20100055145 Betts et al. Mar 2010 A1
20100055294 Wang et al. Mar 2010 A1
20100063570 Pacetti et al. Mar 2010 A1
20100063580 McClain et al. Mar 2010 A1
20100074934 Hunter Mar 2010 A1
20100131044 Patel May 2010 A1
20100155496 Stark et al. Jun 2010 A1
20100166869 Desai et al. Jul 2010 A1
20100196482 Radovic-Moreno et al. Aug 2010 A1
20100198330 Hossainy et al. Aug 2010 A1
20100198331 Rapoza et al. Aug 2010 A1
20100211164 McClain et al. Aug 2010 A1
20100228348 McClain et al. Sep 2010 A1
20100233332 Xing et al. Sep 2010 A1
20100239635 McClain et al. Sep 2010 A1
20100241220 McClain et al. Sep 2010 A1
20100256746 Taylor et al. Oct 2010 A1
20100256748 Taylor et al. Oct 2010 A1
20100272775 Cleek et al. Oct 2010 A1
20100272778 McClain et al. Oct 2010 A1
20100298928 McClain et al. Nov 2010 A1
20100305689 Venkatraman et al. Dec 2010 A1
20110009953 Luk et al. Jan 2011 A1
20110034422 Kannan et al. Feb 2011 A1
20110159069 Shaw et al. Jun 2011 A1
20110160751 Granja Filho Jun 2011 A1
20110172763 Ndondo-Lay Jul 2011 A1
20110190864 McClain et al. Aug 2011 A1
20110223212 Taton et al. Sep 2011 A1
20110238161 Fulton et al. Sep 2011 A1
20110257732 McClain et al. Oct 2011 A1
20110264190 McClain et al. Oct 2011 A1
20110301697 Hoffmann et al. Dec 2011 A1
20120064124 McClain et al. Mar 2012 A1
20120064143 Sharp et al. Mar 2012 A1
20120065723 Drasler et al. Mar 2012 A1
20120101566 Mews et al. Apr 2012 A1
20120150275 Shaw-Klein Jun 2012 A1
20120160408 Clerc et al. Jun 2012 A1
20120172787 McClain et al. Jul 2012 A1
20120177742 McClain et al. Jul 2012 A1
20120271396 Zheng et al. Oct 2012 A1
20120280432 Chen et al. Nov 2012 A1
20120323311 McClain et al. Dec 2012 A1
20130006351 Taylor et al. Jan 2013 A1
20130035754 Shulze et al. Feb 2013 A1
20130087270 Hossainy et al. Apr 2013 A1
20130172853 McClain et al. Jul 2013 A1
20140343667 McClain Nov 2014 A1
20140350522 McClain et al. Nov 2014 A1
20140371717 McClain et al. Dec 2014 A1
20150024116 Matson et al. Jan 2015 A1
20150025620 Taylor et al. Jan 2015 A1
Foreign Referenced Citations (162)
Number Date Country
2237466 Nov 1998 CA
2589761 Jun 2006 CA
2615452 Jan 2007 CA
2650590 Nov 2007 CA
2679712 Jul 2008 CA
2684482 Oct 2008 CA
2721832 Dec 2009 CA
2423899 Mar 2001 CN
1465410 Jan 2004 CN
1575860 Feb 2005 CN
1649551 Aug 2005 CN
1684641 Oct 2005 CN
101161300 Apr 2008 CN
102481195 May 2012 CN
4336209 Mar 1995 DE
29702671 Apr 1997 DE
29716476 Dec 1997 DE
19633901 Feb 1998 DE
29716467 Feb 1998 DE
19740506 Mar 1998 DE
19754870 Aug 1998 DE
19822157 Nov 1999 DE
69611186 May 2001 DE
0335341 Oct 1989 EP
0604022 Jun 1994 EP
800801 Oct 1997 EP
0876806 Nov 1998 EP
0982041 Mar 2000 EP
1195822 Apr 2002 EP
1325758 Jul 2003 EP
1327422 Jul 2003 EP
1454677 Sep 2004 EP
1502655 Feb 2005 EP
1909973 Apr 2008 EP
2197070 Jun 2010 EP
2293357 Mar 2011 EP
2293366 Mar 2011 EP
2758253 Jul 1998 FR
698902 Apr 1994 JP
H06218063 Aug 1994 JP
H08206223 Aug 1996 JP
H0956807 Mar 1997 JP
H1029524 Feb 1998 JP
H10151207 Jun 1998 JP
H10314313 Dec 1998 JP
H1157018 Mar 1999 JP
2000316981 Nov 2000 JP
2001521503 Nov 2001 JP
2003205037 Jul 2003 JP
2003533286 Nov 2003 JP
2003533492 Nov 2003 JP
2003533493 Nov 2003 JP
2004512059 Apr 2004 JP
2004173770 Jun 2004 JP
2004518458 Jun 2004 JP
2004528060 Sep 2004 JP
2004529674 Sep 2004 JP
2005505318 Feb 2005 JP
2005519080 Jun 2005 JP
2005523119 Aug 2005 JP
2005523332 Aug 2005 JP
2005296690 Oct 2005 JP
2006506191 Feb 2006 JP
2006512175 Apr 2006 JP
2007502281 Feb 2007 JP
2009501566 Jan 2009 JP
2010052503 Mar 2010 JP
1020040034064 Apr 2004 KR
9409010 Apr 1994 WO
9506487 Mar 1995 WO
9616691 Jun 1996 WO
9620698 Jul 1996 WO
9632907 Oct 1996 WO
9641807 Dec 1996 WO
9745502 Dec 1997 WO
9802441 Jan 1998 WO
9908729 Feb 1999 WO
9915530 Apr 1999 WO
9916388 Apr 1999 WO
9917680 Apr 1999 WO
0006051 Feb 2000 WO
0025702 May 2000 WO
0032238 Jun 2000 WO
0114387 Mar 2001 WO
0154662 Aug 2001 WO
0187345 Nov 2001 WO
0187368 Nov 2001 WO
0187371 Nov 2001 WO
0187372 Nov 2001 WO
0240702 May 2002 WO
0243799 Jun 2002 WO
02055122 Jul 2002 WO
02074194 Sep 2002 WO
02090085 Nov 2002 WO
02100456 Dec 2002 WO
03039553 May 2003 WO
03082368 Oct 2003 WO
03090684 Nov 2003 WO
03101624 Dec 2003 WO
2004009145 Jan 2004 WO
2004028406 Apr 2004 WO
2004028589 Apr 2004 WO
2004043506 May 2004 WO
2004045450 Jun 2004 WO
2004098574 Nov 2004 WO
2005042623 May 2005 WO
2005063319 Jul 2005 WO
2005069889 Aug 2005 WO
2005117942 Dec 2005 WO
2006014534 Feb 2006 WO
2006052575 May 2006 WO
2006063430 Jun 2006 WO
2006065685 Jun 2006 WO
2006083796 Aug 2006 WO
2006099276 Sep 2006 WO
2007002238 Jan 2007 WO
2007011707 Jan 2007 WO
2007011708 Jan 2007 WO
2007017707 Jan 2007 WO
2007017708 Jan 2007 WO
2007092179 Aug 2007 WO
2007127363 Nov 2007 WO
2007143609 Dec 2007 WO
2008042909 Apr 2008 WO
2008046641 Apr 2008 WO
2008046642 Apr 2008 WO
2008052000 May 2008 WO
2008070996 Jun 2008 WO
2008086369 Jul 2008 WO
2008131131 Oct 2008 WO
2008148013 Dec 2008 WO
2009039553 Apr 2009 WO
2009051614 Apr 2009 WO
2009051780 Apr 2009 WO
2009146209 Dec 2009 WO
2010009335 Jan 2010 WO
2010075590 Jul 2010 WO
2010111196 Sep 2010 WO
2010111232 Sep 2010 WO
2010111238 Sep 2010 WO
2010120552 Oct 2010 WO
2010121187 Oct 2010 WO
2010136604 Dec 2010 WO
2011009096 Jan 2011 WO
2011097103 Aug 2011 WO
2011119762 Sep 2011 WO
2011130448 Oct 2011 WO
2011133655 Oct 2011 WO
2012009684 Jan 2012 WO
2012034079 Mar 2012 WO
2012082502 Jun 2012 WO
2012092504 Jul 2012 WO
2012142319 Oct 2012 WO
2012166819 Dec 2012 WO
2013012689 Jan 2013 WO
2013025535 Feb 2013 WO
2013059509 Apr 2013 WO
2013173657 Nov 2013 WO
2013177211 Nov 2013 WO
2014063111 Apr 2014 WO
2014165264 Oct 2014 WO
2014186532 Nov 2014 WO
Non-Patent Literature Citations (213)
Entry
Jensen et al., Neointimal hyperplasia after sirollmus-eluting and paclitaxel-eluting stend implantation in diabetic patients: the randomized diabetes and dmg eluting stent (DiabeDES) intravascular ultrasound trial. European heartjoumal (29), pp. 2733-2741. Oct. 2, 2008. Retrieved from the Internet. Retrieved on [ Jul. 17, 2012]. URL: <http :/ /eurheartj .oxfordjournals.org/ content/2 9/22/2 73 3. full. pdf> entire document.
Jewell, et al., “Release ofPlasmid DNA from Intravascular Stents Coated with Ultrathin Multilayered Polyelectrolyte Films” Biomacromolecules. 7: 2483-2491 (2006).
Johns, H.E., J.R.Cunnigham, Thomas, Charles C., Publisher, “The Physics of Radiology,” 1983, Springfield, IL, pp. 133-143.
Joner et al. “Site-specific targeting of nanoparticle prednisolone reduces in-stent restenosis in a rabbit model of established atheroma,” Arterioscler Thromb Vase Biol.2008 ;28: 1960-1966.
Jovanovic et al. “Stabilization of Proteins in Dry Powder Formulations Using Supercritical Fluid Technology,” Pharm. Res. 2004; 21(11).
Ju et al., J. Pharm. Sci. vol. 84, No. 12, 1455-1463.
Kazemi et al., “The effect ofbetamethasone gel in reducing sore throat, cough, and hoarseness after laryngo-tracheal intubation,” Middle East J. Anesthesiol. 19(1):197-204 (2007).
Kehinde et al., “Bacteriology of urinary tract infection associated with indwelling J ureteral stents,” J. Endourol. 18 (9):891-896 (2004).
Kelly et al., “Double-balloon trapping technique for embolization of a large widenecked superior cerebellar artery aneurysm: case report,” Neurosurgery 63(4 Suppl 2):291-292 (2008).
Khan et al., “Chemistry and the new uses or Sucrose: How Important?” Pur and Appl. Chem (1984) 56:833-844.
Khan et al., “Enzymic Regioselective Hydrolysis of Peracctylated Reducing Disaccharides, Specifically at the Anomeric Centre: Intermediates for the Synthesis of Oligosaccharides.” Tetrahedron Letters (1933) 34:7767.
Khan et al., Cyclic Acetals of 4,1′,6′-Trichloro-4,1′,6′,-Trideoxy-Trideoxy-galacto-Sucrose and their Conversion into Methyl Ether Derivatives. Carb. ResCarb. Res. (1990) 198:275-283.
Khayankarn et al., “Adhesion and Permeability of Polyimide-Clay Nanocomposite Films for Protective Coatings,” Journal of Applied Polymer Science, vol. 89,2875-2881 (2003).
Koh et al., “A novel nanostructured poly(lactic-co-glycolic-acid) multi-walled carbon nanotube composite for blood-contacting application. Thrombogenicity studies”, Acta Biomaterials 5 (2009): 3411-3422.
Kurt et al., “Tandem oral, rectal and nasal administrations of Ankaferd Blood Stopper to control profuse bleeding leading to hemodynamic instability,” Am J. Emerg. Med. 27(5):631, e1-2 (2009).
Labhasetwar et al., “Arterial uptake of biodegradable nanoparticles: effect of surface modifications,” Journal of Pharmaceutical Sciences, vol. 87, No. 10, Oct. 1998; 1229-1234.
Lamm et al., “Bladder Cancer: Current Optimal Intravesical Treatment: Pharmacologic Treatment,” Urologic Nursing 25 (5):323-6, 331-2 (Oct. 26, 2005).
Latella et al., “Nanoindentation hardness. Young's modulus, and creep behavior of organic-inorganic silica-based sol-gel thin films on copper,” J Mater Res 23(9): 2357- 2365 (2008).
Lawrance et al., “Rectal tacrolimus in the treatment of resistant ulcerative proctitis,” Aliment. Pharmacol Ther. 28 (10):1214-20 (2008).
Lee et al., “Novel therapy for hearing loss: delivery of insulin -like growth factor 1 to the cochlea using gelatin hydrogel, ” Otol. Neurotol. 28(7):976-81 (2007).
Lehmann et al, “Drug treatment of nonviral sexually transmitted diseases: specific issues in adolescents,” Paediatr Drugs 3(7):481-494 (2001).
Lewis, D. H., “Controlled Release of Bioactive Agents from Lactides/Glycolide Polymers” in Biodegradable Polymers as Drug Delivery Systems, Chasin, M. and Langer, R., eds., Marcel Decker (1990).
Luzzi, L.A., J. Phann. Psy. 59:1367 (1970).
Mahoney et al., “Three-Dimensional Compositional Analysis ofDmg Eluting Stent Coatings Using Cluster Secondary Ion mass Spectrometry,” Anal. Chem. , 80, 624-632 (2008).
Matsumoto, D, et al. Neointimal Coverage of Sirolimus-Eluting Stents at 6-month Follow-up: Evaluated by Optical coherence Tomography, European Heart Journal, Nov. 29, 2006; 28:961-967.
McAlpine, J.B. et al., “Revised NMR Assignments for Rapamycine,” J. Antibiotics 44:688-690 (1991).
Mehik et al., “Alfuzosin treatment for chronic prostatitis/chronic pelvic pain syndrome: a prospecitve, randomized, double-blind, placebo-controlled, pilot study,” Urology 62(3):425-429 (2003).
Mei et al., “Local Delivery of Modified Paclitaxel-Loaded Poly(£-caprolactone)/Pluronic F68 Nanoparticles for Long-Term Inhibition of Hyperplasia,” Journal of Pharmaceutical Sciences, Vol. 98, No. 6, June 2009.
Melonakos et al., Treatment of low-grade bulbar transitional cell carcinoma with urethral instillation ormitmnycin C, Oct. 28, 2008, Adv. Urol., 173694 Epub.
Merrett et al., “Interaction of corneal cells with transforming growth factor beta2—modified poly dimethyl siloxane surfaces,” Journal of Biomedical Materials Research, Part A, vol. 67A, No. 3, pp. 981-993 (2003).
Merriam-Webster Online Dictionary, obtained online at: <http://www.merriamwebster.com/dictionay/derivative>, downloaded Jan. 23, 2013.
Middleton and Tipton, Synthetic biodegradable polymers as orthopedic devises. Biomaterials 2000; 21:2335-46.
Minchin, “Nanomedicine: sizing up targets with nanoparticles,” Nature Nanotechnology, vol. 33, Jan. 2008, 12-13.
Minoque et al., “Laryngotracheal topicalization with lidocaine before intubation decreases the incidence of coughing on emergence from general anesthesia,” Anesth. Analg. 99(4):1253-1257 (2004).
Mishima et al. “Microencapsulation of Proteins by Rapid Expansion orSupercritical Solution with a Nonsolvent,” AlChE J. 2000;46(4):857-65.
Mocco et al., “Pharos neurovascular intracranail stent: Elective use for a symptomatic stenosis refractory to medical therapy,” Catheter Cardiovasc. Interv. (epub) (Mar. 2009).
Mollen et al., “Prevalence oftubo-ovarian abcess in adolescents diagnosed with pelvice inflammatory disease in a pediatric emergency department,” Pediatr. Emerg. Care, 22(9): 621-625 (2006).
Moroni et al., “Post-ischemic brain damage:targeting PARP-1 within the ischemic neurovaschular units as a realistic avenue to stroke treatment,” FEBS J. 276(1 ):36-45 (2009).
Muhlen et al., “Magnetic Resonance Imaging Contrast Agent Targeted Toward Activated Platelets Allows in Vivo Detection of Thrombosis and Monitoring of Thrombolysis Circulation,” 118:258-267 (2008).
Murphy et al., “Chronic prostatitis: management strategies,” Drugs 69(1): 71-84 (2009).
O'Donnell et al., “Salvage intravesical therapy with interferon-alpha 2b plus low dose bacillus Calmette-Guerin is affective in patients with superficial bladder cancer in whom bacillus calmette-guerin alone previously failed,” Journ. Urology, 166(4): 1300-1304 (2001).
O'Neil et al., “Extracellular matrix binding mixed micelles for drug delivery applications,” Journal of Controlled Release 137 (2009) 146-151.
Olbert et al., “In vitro and in vivo effects of CpG-Oligodeoxynucleotides (CpG-ODN) on murine transitional cell aarcinoma and on the native murine urinary bladder wall,” Anticancer Res. 29(6):2067-2076 (2009).
Ong and Serruys, “Technology Insight: an overview of research in drug-eluting stents,” Nat. Clin. Parct. Cardiovas. Med. 2(12):647 (2005).
Park et al., Pharm. Res. (1987) 4(6):457-464.
PCT/EP01/05736 International Preliminary Examination Report dated Jan. 14, 2002.
PCT/EP2000/004658 International Search Report from dated Sep. 15, 2000.
PCT/US06/24221 International Preliminary Report on Patentability dated Dec. 24, 2007.
PCT/US06/24221 International Search Report mailed Jan. 29, 2007.
PCT/US06/27321 International Preliminary Report on Patentability dated Jan. 16, 2008.
PCT/US12/33367 International Search Report mailed Aug. 1, 2012.
PCT/US12/40040 International Search Report mailed Sep. 7, 2012.
PCT/US12/46545 International Search Report mailed Nov. 20, 2012.
PCT/US12/50408 International Search Report mailed Oct. 16, 2012.
PCT/US12/60896 International Search Report and Written Opinion dated Dec. 28, 2012.
PCT/US13/41466 International Preliminary Report on Patentability dated Nov. 18, 2014.
PCT/US13/41466 International Search Report and Written Opinion dated Oct. 17, 2013.
PCT/US13/42093 International Preliminary Report on Patentability dated Nov. 25, 2014.
PCT/US13/42093 International Search Report and Written Opinion dated Oct. 24, 2013.
PCT/US13/65777 International Search Report and Written Opinion dated Jan. 29, 2014.
PCT/US14/25017 International Search Report and Written Opinion dated Jul. 7, 2014.
PCT/US14/38117 International Search Report and Written Opinion dated Oct. 7, 2014.
Perry et al., Chemical Engineer's Handbook, 5th Edition, McGraw-Hill, New York, 1973; 20-106.
Plas et al., “Tubers and tumors: rapamycin therapy for benign and malignant tumors”, Curr Opin Cell Bio 21:230-236, (2009).
Poling et al., The Properties of Gases and Liquids. McGraw-Hill. 2001; 9:1-9.97.
Pontari, “Chronic prostatitis/chronic pelvic pain syndrome in elderly men: toward better understanding and treatment,” Drugs Aging 20(15): 1111-1115 (2003).
Pontari, “Inflammation and anti-inflammatory therapy in chronic prostatits,” Urology 60(6Suppl):29-33 (2002).
Putkisto, K. et al. “Polymer Coating of Paper Using Dry Surface Treatment- Coating Structure and Performance”, ePlace newsletter, Apr. 12, 2004, vol. 1, No. 8, pp. 1-20.
Ranade et al., “Physical characterization of controlled release of paclitaxel from the TAXUS Express2 drug-eluting stent,” J. Biomed Mater. Res. 71 (4):625-634 (2004).
Ranganath et al., “Hydrogel matrix entrapping PLGA-paclitaxel microspheres: drug delivery with near zero-order release and implantability advantages for malignant brain tumour chemotherapy,” Pharm Res (Epub) Jun. 20, 2009).
Reddy et al., “Inhibition of apoptosis through localized delivery of rapamycin—loaded nanoparticles prevented neointimal hyperplasia and reendothelialized injured artery,” Circ Cardiovasc Intery 2008;1 ;209-216.
Ristikankare et al., “Sedation, topical phamygeal anesthesia and cardiorespiratory safety during gastroscopy,” J. Clin Gastorenterol. 40(1 ):899-905 (2006).
Sahajanand Medical Technologies (Supralimus Core; Jul. 6, 2008).
Salo et al., “Biofilm formation by Escherichia coli isolated from patients with urinary tract infections,” Clin Nephrol. 71 (5):501-507 (2009).
Saxena et al., “Haemodialysis catheter-related bloodstream infections: current treatment options and strategies for prevention,” Swiss Med Wkly 135:127-138 (2005).
Schetsky, L. McDonald, “Shape Memory Alloys”, Encyclopedia of Chemical Technology (3d Ed), John Wiley & Sons 1982, vol. 20 pp. 726-736.
Scheufler et al., “Crystal Structure of Human Bone Morphogenetic Protein-2 at 27 Angstrom resolution,” Journal of Molecular Biology, vol. 287, Issue 1, Mar. 1999, pp. 103-115, [retrieved online] at http://www.sciencedirect.comIscience/article/pii/S002283 699925901.
Schmidt et al., “A Comparison of the Mechanical Performance Characteristics of Seven Drug-Eluting Stent Systems,” Catheterization and Cardiovascular Interventions 73:350-360 (2009).
Schmidt et al., “In vitro measurement of quality parameters of stent-catheter systems,” Biomed Techn 50 (Si):1505-1506 (2005).
Schmidt et al., “New aspects of in vitro testing of arterial stents based on the new European standard,” EN 14299, [online] (2009), [retrieved on Mar. 10, 2001] <http://www.libOev .de/pl/pdf/EN14 299. pdf> (2009).
Schmidt et al., “Trackability, Crossability, and Pushability of Coronary Stent Systems—An Experimental Approach,” Biomed Techn 47 (2002), Erg. 1, S. 124-126.
Schreiber, S.L. et al., “Atomic Structure of the Rapamycin Human Immunophilin FKBP-12 Complex,” J. Am. Chern. Soc. 113:7433-7435 (1991).
Sen et al., “Topical heparin: A promising agent for the prevention of tracheal stenosis in airway surgery,” J. Surg. Res (Epub ahead of print) Feb. 21, 2009.
Serruys, Patrick et al., Comparison of Coronary-Artery Bypass Surgery and Stenting for the Treatment of Multivessel Disease, N. Engl. J. Med., 2001, vol. 344, No. 15, pp. 1117-1124.
Shekunov et al., “Crystallization Processes in Pharmaceutical Technology and Drup Delivery Design”, Journal of crystal Growth 211 (2000), pp. 122-136.
Simpson et al., “Hyaluronan and hyaluronidase in genitourinary tumors.”Front Biosci. 13:5664-5680.
Smith et al., “Mitomycin C and the endoscopic treatment of laryngotracheal stenosis: Are two applications better than one?” Laryngoscope 119(2):272-283 (2009).
Sumathi et al., “Controlled comparison between betamethasone gel and lidocaine jelly applied over tracheal tube to reduce postoperative sore throat, cough, and hoarseness of voice,” Br. J. Anaesth. 100(2):215-218 (2008).
Szabadits et al., “Flexibility and trackability of laser cut coronary stent systems,” Acta of Bioengineering and Biomechanics 11 (3 ): 11-18 (2009).
Testa, B., “Prodrug research: futile or fertile?”, Biochem. Pharmacal. Dec. 1, 2004;68(11):2097-2106.
Thalmann et al., “Long-term experience with bacillus Calmette-Guerin therapy of upper urinary tract transitional cell carcinoma in patients not eligible for surgery,” J Urol. 168(4 Pt 1):1381-1385 (2002).
Torchlin, “Micellar Nanocarriers: Pharmaecutial Perspectives,” Pharmaceutical Research, vol. 24, No. 1, Jan. 2007.
Unger et al., “Poly(ethylene carbonate): A thermoelastic and biodegradable biomaterial for drug eluting stent coatings?” Journal to Controlled Release, vol. 117, Issue 3, 312-321 (2007).
Verma et al., “Effect of surface properties on nanoparticle-cell interactions,” Small 2010,6,No. 1, 12-21.
Wagenlehner et al., “A pollen extract (Cemilton) in patients with inflammatory chronic prostatitis/chronic pelvic pain syndrome: a multicentre, randomized, prospective, double-blind, placebo-controlled phase 3 study,” Eur Urol 9 (Epub) (Jun. 3, 2009).
Wang et al. “Synthesis, characterization, biodegradation, and drug delivery application of biodegradable lactic/glycolic acid polymers: I. Synthesis and characterization” J. Biomater. Sci. Polymer Edn. 11(3):301-318 (2000).
Wang et al., “Treatment with melagatran alone or in combination with thrombolytic therapy reduced ischemic brain Injury,” Exp. Neuro. 213(1):171-175 (2008).
Wang, X.; Venkatraman, S.S.; Boey, F.Y.C.; Loo, J.S.C.; Tan, L.P. “Controlled release of sirolimus from a multilayered PLGA stent matrix” Biomaterials 2006, 27, 5588-5595.
Warner et al., “Mitomycin C and airway surgery: how well does it work?” Ontolaryngol Head Neck Surg. 138 (6):700-709 (2008).
Wermuth, CG, “Similarity in drugs: reflections on analogue design”, Drug Discov Today. Apr. 11, 2006 (7-8):348-54.
PCT/US06/27321 International Search Report mailed Oct. 16, 2007.
PCT/US06/27321 Written Opinion dated Oct. 16, 2007.
PCT/US06/27322 International Preliminary Report on Patentability dated Jan. 16, 2008.
PCT/US06/27322 International Search Report mailed Apr. 25, 2007.
PCT/US07/10227 International Preliminary Report on Patentability dated Oct. 28, 2008.
PCT/US07/10227 International Search Report mailed Aug. 8, 2008.
PCT/US07/80213 International Preliminary Report on Patentability dated Apr. 7, 2009.
PCT/US07/80213 International Search Report mailed Apr. 16, 2008.
PCT/US07/82275 International Search Report mailed Apr. 18, 2008.
PCT/US07/82775 International Preliminary Report on Patentablity dated May 5, 2009.
PCT/US08/11852 International Preliminary Report on Patentability dated Apr. 20, 2010.
PCT/US08/11852 International Search Report mailed Dec. 19, 2008.
PCT/US08/50536 International Preliminary Report on Patentability dated Jul. 14, 2009.
PCT/US08/50536 International Search Report mailed Jun. 2, 2008.
PCT/US08/60671 International Preliminary Report on Patentability dated Oct. 20, 2009.
PCT/US08/60671 International Search Report mailed Sep. 5, 2008.
PCT/US08/64732 International Preliminary Report on Patentability dated Dec. 1, 2009.
PCT/US08/64732 International Search Report mailed Sep. 4, 2008.
PCT/US09/41045 International Preliminary Report on Patentability dated Oct. 19, 2010.
PCT/US09/41045 International Search Report mailed Aug. 11, 2009.
PCT/US09/50883 International Preliminary Report on Patentability dated Jan. 18, 2011.
PCT/US09/50883 International Search Report mailed Nov. 17, 2009.
PCT/US09/69603 International Preliminary Report on Patentability dated Jun. 29, 2011.
PCT/US09/69603 International Search Report mailed Nov. 5, 2010.
PCT/US10/28195 International Preliminary Report on Patentability dated Sep. 27, 2011.
PCT/US10/28195 Search Report and Written Opinion mailed Jan. 21, 2011.
PCT/US10/28253 International Preliminary Report on Patentability dated Sep. 27, 2011.
PCT/US10/28253 Search Report and Written Opinion mailed Dec. 6, 2010.
PCT/US10/28265 International Report on Patentability dated Sep. 27, 2011.
PCT/US10/28265 Search Report and Written Opinion mailed Dec. 13, 2010.
PCT/US10/29494 International Preliminary Report on Patentability dated Oct. 4, 2011.
PCT/US10/29494 Search Report and Written Opinion mailed Feb. 7, 2011.
PCT/US10/31470 International Preliminary Report on Patentability dated Oct. 18, 2011.
PCT/US10/31470 Search Report and Written Opinion mailed Jan. 28, 2011.
PCT/US10/42355 International Preliminary Report on Patentability dated Jan. 17, 2012.
PCT/US10/42355 Search Report mailed Sep. 2, 2010.
PCT/US11/22623 International Preliminary Report on Patentability dated Aug. 7, 2012.
PCT/US11/22623 Search Report and Written Opinion mailed Mar. 28, 2011.
PCT/US11/29667 International Search Report and Written Opinion mailed Jun. 1, 2011.
PCT/US11/32371 International Report on Patentability dated Oct. 16, 2012.
PCT/US11/32371 International Search Report dated Jul. 7, 2011.
PCT/US11/33225 International Search Report and Written Opinion dated Jul. 7, 2011.
PCT/US11/44263 International Preliminary Report on Patentability dated Jan. 22, 2013.
PCT/US11/44263 International Search Report and Written Opinion dated Feb. 9, 2012.
PCT/US11/51092 International Preliminary Report on Patentability dated Mar. 12, 2013.
PCT/US11/51092 International Search Report dated Mar. 27, 2012.
PCT/US11/51092 Written Opinion dated Mar. 27, 2012.
PCT/US11/67921 International Preliminary Report on Patentability dated Jul. 2, 2013.
PCT/US11/67921 Search Report and Written Opinion mailed Jun. 22, 2012.
PCT/US12/33367 International Preliminary Report on Patentability dated Oct. 15, 2013.
Handschumacher, R.E. et al., Purine and Pyrimidine Antimetabolites, Chemotherapeutic Agents, pp. 712-732, Ch. XV1-2, 3rd Edition, Edited by J. Holland, et al., Lea and Febigol, publishers.
Higuchi, Rate of Release of Medicaments from Ointment Bases Containing Drugs in Suspension, Journal of Pharmaceutical Sciences, vol. 50, No. 10, p. 874, Oct. 1961.
Ji, et al., “96-Wellliquid-liquid extraction liquid chromatographytandem mass spectrometry method for the quantitative letermination of ABT-578 in human blood samples” Journal of Chromatography B. 805:67-75 (2004).
Levit, et al., “Supercritical C02 Assisted Electrospinning” J. of Supercritical Fluids, 329-333, vol. 31, Issue 3, (Nov. 2004).
David Grant, Crystallization Impact on the Nature and Properties of the Crystalline Product, 2003, SSCI, http://www.ssci-inc.com/Information/RecentPublications/ApplicationNotes/CrystallizationImpact/tabid/138/Default.aspx.
Abreu Filho et al., “Influence of metal alloy and the profile of coronary stents in patients with multivessel coronary disease,” Clinics 2011 ;66(6):985-989.
Akoh et al., “One-Stage Synthesis of Raffinose Fatty Acid Polyesters.”Journal Food Science (1987) 52:1570.
Albert et al., “Antibiotics for preventing recurrent urinary tract infection in nonpregnant women,”Cochrane Database System Rev. 3, CD001209 (2004).
Analytical Ultracentrifugation of Polymers and Nanoparticles, W. Machtle and L. Borger, (Springer) 2006, p. 41.
Au et al., “Methods to improve efficacy of intravesical mitomycin C: Results of a randomized phase III trial,” Journal of the National Cancer Institute, 93 (8 ), 597-604 (2001).
Balss et al., “Quantitative spatial distribution of sirolumus and polymers in drugeluting stents using confocal Raman microscopy,” J. of Biomedical Materials Research Part A, 258-270 (2007).
Belu el al., “Three-Dimensional Compositional Analysis of Drug Eluting Stent Coatings Using Cluster Secondary Ioan Mass Spectrometry,” Anal. Chem. 80:624-632 (2008).
Belu, et al., “Chemical imaging of drug eluting coatings: Combining surface analysis and confocal Rama microscopy” J. Controlled Release 126: 111-121 (2008).
Boneff, “Topical Treatment of Chronic Prostatitis and Premature Ejaculation,” International Urology and Nephrology 4(2):183-186 (1971).
Bookbinder et al., “A recombinant human enzyme for enhanced interstitial transport of therapeutics,” Journal of Controlled Release 114:230-241 (2006).
Borchert et al., “Prevention and treatment of urinary tract infection with probiotics: Review and research perspective,” Indian Journal Urol. 24(2): 139-144 (2008).
Brunstein et al., “Histamine, a vasoactive agent with vascular disrupting potential, improves tumour response by enhancing local drug delivery,” British Journal of Cancer 95:1663-1669 (2006).
Bugay et al., “Raman Analysis of Pharmaceuticals,” in “Applications of Vibrational Spectroscopy in Pharmaceutical Research and Development,” Edited by Pivonka, D.E., Chalmers, J.M., Griffiths, P.R. (2007) Wiley and Sons.
Cadieux et al., Use of triclosan-eluting ureteral stents in patients with long-term stents, J. Endourol (Epub) (Jun. 19, 2009).
Chalmers, et al. (2007) Wiley and Sons.
Channon et al., “Nitric Oxide Synthase in Atherosclerosis and Vascular Injury: Insights from Experimental Gene Therapy,” Arteriosclerosis, Thrombosis and Vascular Biology, 20(8):1873-1881 (2000).
Chen et al. Immobilization of heparin on a silicone surface through a heterobifunctional PEG spacer. Biomaterials. Dec. 2005;26(35):7418-24.
Chlopek et al., “The influence of carbon fibres on the resorption time and mechanical properties of the lactide-glycolide co-polymer”, J. Biomater. Sci. Polymer Edn. vol. 18, No. 11, pp. 1355-1368 (2007).
Clair and Burks, “Thermoplastic/Melt-Processable Polyimides,” NASA Conf. Pub. #2334 (1984), pp. 337-355.
Cohen et al., “Sintering Technique for the Preparation of Polymer Matrices for the Controlled Release of Macromolecules”, Journal of Pharmaceutical Sciences, vol. 73, No. 8, 1984, p. 1034-1037.
Colombo et al. “Selection of Coronary Stents,” Journal of the American College of Cardiology, vol. 40, No. 6, 2002, p. 1021-1033.
CRC Handbook of chemistry and physics. 71st ed. David R. Lide, Editor-in -Chief. Boca Raton, FL, CRC Press; 1990; 6-140.
Cyrus et al., “Intramural delivery of rapamycin with alphavbeta3-targeted paramagnetic nanoparticles inhibits stenosis after balloon injury,” Arterioscler Thromb Vasc Biol 2008; 28:820-826.
Derwent—Acc-No. 2004-108578 Abstracting 2004003077; Jan. 8, 2004; 3 pages.
Di Mario, C. et al., “Drug-Eluting Bioabsorbable Magnesium Stent,” J. Interventional Cardiology 16(6):391-395 (2004).
Di Stasi et al., “Percutaneous sequential bacillus Calmette-Guerin and mitomycin C for panurothelial carcinomatosis,” Can. J. Urol. 12(6):2895-2898 (2005).
Domb and Langer, “Polyanhydrides. I. Preparation of High Molecular Weight Polyanhydrides. ”J. Polym Sci. 25:3373-3386 (1987).
Domingo, C., et al., “Precipication of ultrafine organic crystals from the rapid expansion of supercritical solutions ove a capillary and a frit nozzle”, J. Supercritical Fluids 10:39-55 (1997).
Dzik-Jurasz, “Molecular imaging in vivo: an introduction,” The British Journal of Radiology, 76:S98-S109 (2003).
Electrostatic Process, Wiley Encyclopedia of Electrical and Electronics Engineering, John Wiley & Sons, Inc. 1999;7:15-39.
Eltze et al., “Imidazoquinolinon, imidazopyridine, and isoquinolindione derivatives as novel and potent inhibitors ofthe poly (ADP-ribose) polymerase (PARP): a comparison with standard PARP inhibitors,” Mol. Pharmacal 74(6)1587-1598 (2008).
Ettmayer et al. Lessons learned from marketed and investigational prodrugs. J Med Chem. May 6, 2004;47 (10)2393-404.
European International Search Report of PCT/EP01/05736 dated Oct. 24, 2001.
Fibbi et al., “Chronic inflammation in the pathogenesis of benign prostatic hyperplasia,” Int J Androl. Jun. 1, 2010;33 (3)475-88.
Finn et al. Differential Response of Delayed Healing . . . Circulation vol. 112 (2005) 270-8.
Fleischmann et al., “High Expression of Gastrin-Releasing Peptide Receptors in the Vascular bed of Urinary Tract Cancers: Promising Candidates for Vascular Targeting Applications.” Jun. 2009, Endocr. Relat. Cancer 16(2):623-33.
Froehlich et al., “Conscious sedation for gastroscopy: patient tolerance and cardiorespiratory parameters,” Gastroenterology 108(3):697-704 (1995).
Fujiwara et al., “Insulin-like growth factor 1 treatment via hydrogels rescues cochlear hair cells from ischemic injury,” Oct. 29, 2008, NeuroReport 19(16):1585-1588.
Fulton et al. Thin Fluoropolymer films and nanoparticle coatings from the rapid expansion of supercritical carbon dioxide solutions with electrostatic collection, Polymer Communication. 2003; 2627-3632.
Greco et al. (Journal of Thermal Analysis and Calorimetry, vol. 72 (2003) 1167-1174.).
Green et al., “Simple conjugated polymer nanoparticles as biological labels,” Proc Roy Soc A. published online Jun. 24, 2009 doi:10.1098/rspa.2009.0181.
Griebenow et al., “On Protein Denaturation in Aqueous-Organic Mixtures but not in Pure Organic Solvents,” J. Am Chem Soc., vol. 118. No. 47, 11695-11700 (1996).
Hamilos et al., “Ditlerential etlects ofDmg-Eluting Stents on Local Endothelium-Dependent Coronary Vasomotion.” JACC vol. 51, No. 22,2008, Endothelium and DES Jun. 3, 2008:2123-9.
Han, et al., “Studies of a Novel Human Thrombomodulin Immobilized Substrate: Surface Characterization and Anticoagulation Activity Evaluation.” J. Biomater. Sci. Polymer Edn, 2001, 12 (10), 1075-1089.
Hartmann et al., “Tubo-ovarian abscess in virginal adolescents: exposure or the underlying etiology,” J. Pediatr Adolesc Gynecol, 22(3):313-16 (2009).
Hasegawa et al., “Nylong 6/Na-montmorillonite nanocomposites prepared by compounding Nylon 6 with Na-montmorillonite slurry,” Polymer 44 (2003) 2933-2937.
Hinds, WC. Aerosol Technology, Properties, Behavior and Measurement of Airbome Particles, Department of Environmental Health Sciences, Harvard University School of Public Health, Boston, Massachusetts. 1982; 283-314.
Hladik et al., “Can a topical microbicide prevent rectal HIV transmission?” PLoS Med. 5(8):e167 (2008).
Iconomidou et al., “Secondary Structure of Chorion Proteins ofthe Teleosatan Fish Dentex dentex by ATR FR-IR and FT—Raman Spectroscopy,” J. of Structural Biology, 132, 112-122(2000).
Jackson et al., “Characterization of perivascular poly(lactic-co-glycolic acid) films containing paclitaxel” Int. J. ofPhannaceutics, 283:97-109 (2004), incorporated in its entirety herein by reference.
Witjes et al., “Intravesical pharmacotherapy for non-muscle-invasive bladder cancer: a critical analysis of currently available drugs, treatment schedules, and long-term results,” Eur. Urol. 53(1):45-52.
Wu et al., “Study on the preparation and characterization of biodegradable polylactide/multi-walled carbon nanotubes nanocomposites”, Polymer 48 (2007) 4449-4458.
Xu et al., “Biodegradation of poly(L-lactide-co-glycolide) tube stents in bile”, Polymer Degradation and Stability. 93:811-817 (2008).
Xue et al., “Spray-as-you-go airway topical anesthesia in patients with a difficult airway: a randomized, double-blind comparison of2% and 4% lidocaine,” Anesth. blind comparison of 2% and 4% lidocaine, Anesth. Analg. 108(2): 536-543 (2009).
Yepes et al., “Tissue-type plasminogen activator in the ischemic brain: more than a thrombolytic,” Trends Neurosci. 32(1):48-55 (2009).
Yousuf et al., “Resveratrol exerts its neuroprotective effect by modulating mitochondrial dysfunction and associated cell death during cerebral ischemia”, Brain Res. 1250:242-253 (2009).
Zhou, S.; Deng, X.; Li, X.; Jia, W.; Liu, L. “Synthesis and Characterization of Biodegradable Low Molecular Weight Aliphatic Polyesters and Their Use in Protein-Delivery Systems” J. Appl. Polym. Sci. 2004, 91, 1848-1856.
Zilberman et al., Drug-Eluting bioresorbable steuts for various applications, Annu Rev Biomed Eng,., 2006;8:158-180.
Related Publications (1)
Number Date Country
20160101220 A1 Apr 2016 US
Provisional Applications (3)
Number Date Country
60912394 Apr 2007 US
60745731 Apr 2006 US
60745733 Apr 2006 US
Continuations (2)
Number Date Country
Parent 14473741 Aug 2014 US
Child 14969884 US
Parent 12298459 US
Child 14473741 US